Techniques for configuring uplink channels in unlicensed radio frequency spectrum bands

ABSTRACT

Techniques are described for wireless communication. An orthogonal frequency-division multiple access (OFDMA) configuration of an uplink channel is identified for communications in an unlicensed radio frequency spectrum band. An OFDMA waveform is generated based on the identified OFDMA configuration. The OFDMA waveform is communicated in a signal in the unlicensed radio frequency spectrum band. A virtual cell identifier of a first base station may be associated with transmissions between the first base station and a first user equipment (UE). A set of common resource blocks may be identified for transmission of a demodulation reference signal (DM-RS) between the first base station and the first UE. A configuration of an uplink channel may be dynamically selected for uplink communications in an unlicensed radio frequency spectrum band. A waveform may be generated based on the selected configuration. The waveform may be communicated in a signal in the unlicensed radio frequency spectrum band.

CROSS REFERENCES

The present Application for Patent claims priority to U.S. ProvisionalPatent Application No. 61/919,518 by Luo et al., entitled “TechniquesFor Configuring Uplink Channels In Unlicensed Radio Frequency SpectrumBands,” filed Dec. 20, 2013, assigned to the assignee hereof, and whichis hereby incorporated by reference in its entirety.

FIELD OF THE DISCLOSURE

The present disclosure, for example, relates to wireless communicationsystems, more specifically to techniques for configuring uplink channelsin unlicensed radio frequency spectrum bands.

DESCRIPTION OF RELATED ART

Wireless communication systems are widely deployed to provide varioustypes of communication content such as voice, video, packet data,messaging, broadcast, and so on. These systems may be multiple-accesssystems capable of supporting communication with multiple users bysharing the available system resources (e.g., time, frequency, andpower). Examples of such multiple-access systems include code-divisionmultiple access (CDMA) systems, time-division multiple access (TDMA)systems, frequency-division multiple access (FDMA) systems, andorthogonal frequency-division multiple access (OFDMA) systems.

For example, a wireless multiple-access communication system may includea number of base stations, each simultaneously supporting communicationfor multiple user equipments (UEs, such as mobile devices). A basestation may communicate with UEs on downlink channels (e.g., fortransmissions from a base station to a UE) and uplink channels (e.g.,for transmissions from a UE to a base station).

The configuration of an uplink channel may have an impact on one or moremetrics associated with the uplink channel (e.g., metrics related tosymbol power or channel quality). The configuration of an uplink channelmay also impact the ability to cancel interference from other waveformswhen receiving and/or decoding the uplink channel, for example.

SUMMARY

The present disclosure, for example, relates to one or more techniquesfor configuring an uplink channel for uplink communications in anunlicensed radio frequency spectrum band. In some examples, thetechniques may provide for dynamically selecting a configuration of anuplink channel for uplink communications in an unlicensed radiofrequency spectrum band (e.g., a shared radio frequency spectrum bandusable for Wi-Fi and/or LTE/LTE-A communications). The configuration maybe selected, for example, from among an OFDMA configuration, a singlecarrier frequency-division multiple access (SC-FDMA) configuration, anda resource block (RB) interleaved FDMA configuration. In other examples,the techniques may provide for generating and/or communicating an OFDMAwaveform in a signal in the unlicensed radio frequency spectrum bandusing the uplink channel. The OFDMA waveform may be variously configuredfor an uplink channel including a physical uplink shared channel(PUSCH), a physical uplink control channel (PUCCH), and/or a physicalrandom access channel (PRACH), for example. In other examples, thetechniques may provide for interference cancelation when an uplinkchannel is received and/or decoded.

In a first set of illustrative examples, a method for wirelesscommunication is described. In one example, the method may includeidentifying an OFDMA configuration of an uplink channel for uplinkcommunications in an unlicensed radio frequency spectrum band,generating an OFDMA waveform based on the identified OFDMAconfiguration, and communicating the generated OFDMA waveform in asignal in the unlicensed radio frequency spectrum band using the uplinkchannel.

In some examples, the uplink channel may include a Physical UplinkShared Channel (PUSCH). In these examples, the method may furtherinclude allocating resources for the PUSCH based at least in part on abitmap of interlaces or resource blocks, or based at least in part on astarting resource block and a number of resource blocks. In someexamples, the method may include allocating resources for the PUSCHbased at least in part on a starting interlace and a number ofinterlaces, and the interlace may be a pre-defined set of resourceblocks selected to span an entire bandwidth. In some examples,allocating the resources for the PUSCH is for multi-cluster transmissionin which a user equipment is assigned to two or more clusters adjacentto each other. In such a case, the method may include allocatingresources for the PUSCH based in part on two or more of the resourceblocks assigned to the user equipment. The method may also oralternately include mapping one or more modulation symbols to one ormore resource elements according to one or more OFDM symbol positions,or mapping one or more modulation symbols to one or more resourceelements according to one or more frequency sub-carriers, or mapping oneor more modulation symbols to one or more resource elements according toan interleaving of time slots and frequency sub-carriers. The method mayalso or alternately include transmitting a demodulation reference signal(DM-RS) on the uplink channel in a first set of one or more time slotsand one or more first frequency sub-carriers. The first set of one ormore time slots and one or more first frequency sub-carriers may be thesame as a second set of one or more time slots and one or more secondfrequency sub-carriers used to receive a user equipment specificreference signal (UE-RS) on a downlink channel. The method may also oralternately include transmitting a DM-RS on the uplink channel in afirst set of one or more time slots and one or more first frequencysub-carriers. The first set of one or more time slots and one or morefirst frequency sub-carriers may differ in at least one respect from asecond set of one or more time slots and one or more second frequencysub-carriers used to receive a UE-RS on a downlink channel.

In some examples, the method may include using PRB bundling whengenerating the OFDMA waveform based on the identified OFDMAconfiguration. The method may also or alternately include using precodercycling when generating the OFDMA waveform based on the identified OFDMAconfiguration, wherein a precoder may be cycled through a pre-definedset of precoders. The precoder used for the precoder cycling may beindicated by a base station as part of an uplink grant. In someexamples, the precoder may be derived by a UE based at least in part ondownlink channel state information reference signal (CSI-RS)transmissions. [0010] In some examples, the uplink channel may includean uplink multiple-input multiple-output (UL-MIMO) channel or amulti-user MIMO (MU-MIMO) channel.

In some examples, the method may include applying symbol permutation orphase rotation to reduce a metric indicating symbol power whengenerating the OFDMA waveform based on the identified OFDMAconfiguration. The method may also or alternately include applyingdifferent scrambling sequences to the OFDMA waveform, and selecting oneof the scrambling sequences for use when communicating the generatedOFDMA waveform in the signal in the unlicensed radio frequency spectrumband.

In some examples, the uplink channel may include a Physical UplinkControl Channel (PUCCH). In these examples, communicating the generatedOFDMA waveform in a signal in the unlicensed radio frequency spectrumband using the uplink channel may include transmitting duplicate copiesof the PUCCH in a plurality of interleaved resource blocks.Communicating the generated OFDMA waveform in a signal in the unlicensedradio frequency spectrum band using the uplink channel may also oralternately include multiplexing the PUCCH within a plurality ofinterleaved resource blocks according to a code division multiplexingsequence or other orthogonal sequence. Communicating the generated OFDMAwaveform in a signal in the unlicensed radio frequency spectrum bandusing the uplink channel may also or alternately include multiplexingthe PUCCH within a plurality of resource elements of an enhancedresource element group.

In some examples, the uplink channel may include a Physical RandomAccess Channel (PRACH) transmitted on one or more pre-allocatedinterlaces.

In some examples, the method may include transmitting a soundingreference signal (SRS) on the uplink channel. The SRS may be located inan OFDM symbol position of a subframe that is different from a last OFDMsymbol position of the subframe. In other examples, the method mayinclude communicating the generated OFDMA waveform without an SRS in thesignal in the unlicensed radio frequency spectrum band using the uplinkchannel.

In some examples, the method may include transmitting a channel stateinformation reference signal (CSI-RS) in the uplink channel, independentof an allocation of resources and on all resource blocks. In someexamples, the CSI-RS may be transmitted depending on a resourceallocation. In these examples, the method may include indicating a ratematching for a PUSCH and a PUCCH to accommodate transmission of theCSI-RS. The method may also or alternately include transmitting achannel state information interference measurement (CSI-IM) in theuplink channel. In some examples, the method may further includegenerating, by a base station, a precoder to be used in a downlinkchannel based at least in part on the uplink CSI-RS transmission.

In some examples, the method may include using a first set of resourceblocks to transmit the uplink channel when the uplink channel comprisesa PUCCH but not a PUSCH, and using a second set of resource blocks totransmit the uplink channel when the uplink channel comprises the PUSCHbut not the PUCCH. The second set of resource blocks may be differentthan the first set of resource blocks. In these examples, and when theuplink channel comprises the PUCCH and the PUSCH, the method may furtherinclude frequency division multiplexing the PUCCH and the PUSCH on theuplink channel, using a subset of less than all of the first set ofresource blocks to transmit the PUCCH, and using at least some of thesecond set of resource blocks to transmit the PUSCH. When the PUCCH andthe PUSCH are frequency division multiplexed, the method may alsoinclude using at least one of the first set of resource blocks totransmit the PUSCH. Also or alternately, when the uplink channelincludes the PUCCH and the PUSCH, the method may include frequencydivision multiplexing the PUCCH and the PUSCH by puncturing at least onefrequency sub-input of at least one resource block of the first set ofresource blocks to transmit at least part of the PUSCH.

In some examples, the method may include frequency division multiplexinga PUCCH and a PUSCH on the uplink channel, transmitting acknowledgementspertaining to a Physical Downlink Shared Channel (PDSCH) as part of thePUCCH, and transmitting channel quality information (CQI) as part of thePUSCH. In some examples, transmitting the CQI as part of the PUSCH mayinclude transmitting CQI of a plurality of downlink carrierssimultaneously.

In some examples, the method may include receiving signaling from a basestation, and selecting the OFDMA configuration of the uplink channelbased at least in part on the received signaling. In these examples, thesignaling from the base station may indicate a resource blockallocation, and the OFDMA configuration of the uplink channel may beselected based at least in part on the resource block allocation. Insome examples, the OFDMA configuration of the uplink channel may beselected based at least in part on a modulation and coding scheme (MCS)indicated in a downlink grant received from the base station. In someexamples, the OFDMA configuration of the uplink channel may be selectedbased at least in part on whether an uplink multiple-inputmultiple-output (UL-MIMO) or multi-user MIMO (MU-MIMO) is enabled ordisabled.

In a second set of illustrative examples, an apparatus for wirelesscommunication is described. In one example, the apparatus may includemeans for identifying an OFDMA configuration of an uplink channel foruplink communications in an unlicensed radio frequency spectrum band,means for generating an OFDMA waveform based on the identified OFDMAconfiguration, and means for communicating the generated OFDMA waveformin a signal in the unlicensed radio frequency spectrum band using theuplink channel. In certain examples, the apparatus may further includemeans for implementing one or more aspects of the method for wirelesscommunication described above with respect to the first set ofillustrative examples.

In a third set of illustrative examples, another apparatus for wirelesscommunication is described. In one example, the apparatus may include aprocessor, memory in electronic communication with the processor, andinstructions stored in the memory. The instructions may be executable bythe processor to identify an OFDMA configuration of an uplink channelfor uplink communications in an unlicensed radio frequency spectrumband, generate an OFDMA waveform based on the identified OFDMAconfiguration, and communicate the generated OFDMA waveform in a signalin the unlicensed radio frequency spectrum band using the uplinkchannel. In certain examples, the instructions may also be executable bythe processor to implement one or more aspects of the method forwireless communication described above with respect to the first set ofillustrative examples.

In a fourth set of illustrative examples, a computer program product forcommunication by a wireless communications apparatus in a wirelesscommunications network is described. In one example, the computerprogram product may include a non-transitory computer-readable mediumstoring computer-executable code for wireless communications, the codeexecutable by a processor to identify an OFDMA configuration of anuplink channel for uplink communications in an unlicensed radiofrequency spectrum band, generate an OFDMA waveform based on theidentified OFDMA configuration, and communicate the generated OFDMAwaveform in a signal in the unlicensed radio frequency spectrum bandusing the uplink channel. In certain examples, the code may also beexecutable by the processor to implement one or more aspects of themethod for wireless communication described above with respect to thefirst set of illustrative examples.

In a fifth set of illustrative examples, another method for wirelesscommunication is described. In one example, the method may includeassociating a virtual cell identifier of a first base station withtransmissions between the first base station and a first UE. The virtualcell identifier may also be associated with transmissions between asecond base station and a second UE. The method may also includeidentifying a set of common resource blocks for transmission of a DM-RSin an uplink channel and a downlink channel between the first basestation and the first UE. The identification of the set of commonresource blocks may be based at least in part on the virtual cellidentifier.

In some examples, the method may include identifying a first portassociated with a first spatial multiplexing for transmission of theDM-RS between the first base station and the first UE. The first spatialmultiplexing may be different from a second spatial multiplexingassociated with a second port used to transmit a DM-RS between thesecond base station and the second UE. In these examples, the method mayfurther include associating a first link identifier with the uplinkchannel between the first base station and the first UE, associating asecond link identifier with the downlink channel between the first basestation and the first UE, and transmitting the first link identifierwith transmissions in the uplink channel or transmitting the second linkidentifier with transmissions in the downlink channel. The first linkidentifier may be different from the second link identifier.Transmitting the first link identifier with transmissions in the uplinkchannel may include generating the DM-RS as a function of the first linkidentifier, and transmitting the second link identifier withtransmissions in the downlink channel may include generating the DM-RSas a function of the second link identifier.

In a sixth set of illustrative examples, another apparatus for wirelesscommunication is described. In on example, the apparatus may includemeans for associating a virtual cell identifier of a first base stationwith transmissions between the first base station and a first UE, andmeans for identifying a set of common resource blocks for transmissionof a DM-RS in an uplink channel and a downlink channel between the firstbase station and the first UE. The virtual cell identifier may also beassociated with transmissions between a second base station and a secondUE. The identification of the set of common resource blocks may be basedat least in part on the virtual cell identifier. In certain examples,the apparatus may further include means for implementing one or moreaspects of the method for wireless communication described above withrespect to the fifth set of illustrative examples.

In a seventh set of illustrative examples, another apparatus forwireless communication is described. In one example, the apparatus mayinclude a processor, memory in electronic communication with theprocessor, and instructions stored in the memory. The instructions maybe executable by the processor to associate a virtual cell identifier ofa first base station with transmissions between the first base stationand a first UE, and identify a set of common resource blocks fortransmission of a DM-RS in an uplink channel and a downlink channelbetween the first base station and the first UE. The virtual cellidentifier may also be associated with transmissions between a secondbase station and a second UE. The identification of the set of commonresource blocks may be based at least in part on the virtual cellidentifier. In certain examples, the instructions may also be executableby the processor to implement one or more aspects of the method forwireless communication described above with respect to the fifth set ofillustrative examples.

In an eighth set of illustrative examples, another computer programproduct for communication by a wireless communications apparatus in awireless communications network is described. In one example, thecomputer program product may include a non-transitory computer-readablemedium storing computer-executable code for wireless communications, thecode executable by a processor to associate a virtual cell identifier ofa first base station with transmissions between the first base stationand a first UE, and identify a set of common resource blocks fortransmission of a DM-RS in an uplink channel and a downlink channelbetween the first base station and the first UE. The virtual cellidentifier may also be associated with transmissions between a secondbase station and a second UE. The identification of the set of commonresource blocks may be based at least in part on the virtual cellidentifier. In certain examples, the code may also be executable by theprocessor to implement one or more aspects of the method for wirelesscommunication described above with respect to the fifth set ofillustrative examples.

In a ninth set of illustrative examples, another method for wirelesscommunication is described. In one example, the method may includedynamically selecting a configuration of an uplink channel for uplinkcommunications in an unlicensed radio frequency spectrum band,generating a waveform based on the selected configuration, andcommunicating the generated waveform in a signal in the unlicensed radiofrequency spectrum band using the uplink channel.

In some examples, the configuration of the uplink channel may beselected from an OFDMA configuration, a single carrierfrequency-division multiple access (SC-FDMA) configuration, and aresource block interleaved frequency-division multiple access (FDMA)configuration.

In some examples, the method may include receiving signaling from a basestation, and selecting the configuration of the uplink channel based atleast in part on the received signaling. In these examples, thesignaling from the base station may indicate a resource blockallocation, and the configuration of the uplink channel may be selectedbased at least in part on the resource block allocation. In someexamples, the configuration of the uplink channel may be selected basedat least in part on a modulation and coding scheme (MCS) indicated in adownlink grant received from the base station. In some examples, theconfiguration of the uplink channel may be selected based at least inpart on whether an uplink multiple-input multiple-output (UL-MIMO) ormulti-user MIMO (MU-MIMO) is enabled or disabled.

In a tenth set of illustrative examples, another apparatus for wirelesscommunication is described. In one example, the apparatus may includemeans for dynamically selecting a configuration of an uplink channel foruplink communications in an unlicensed radio frequency spectrum band,means for generating a waveform based on the selected configuration, andmeans for communicating the generated waveform in a signal in theunlicensed radio frequency spectrum band using the uplink channel. Incertain examples, the apparatus may further include means forimplementing one or more aspects of the method for wirelesscommunication described above with respect to the ninth set ofillustrative examples.

In an eleventh set of illustrative examples, another apparatus forwireless communication is described. In one example, the apparatus mayinclude a processor, memory in electronic communication with theprocessor, and instructions stored in the memory. The instructions maybe executable by the processor to dynamically select a configuration ofan uplink channel for uplink communications in an unlicensed radiofrequency spectrum band, generate a waveform based on the selectedconfiguration, and communicate the generated waveform in a signal in theunlicensed radio frequency spectrum band using the uplink channel. Incertain examples, the instructions may also be executable by theprocessor to implement one or more aspects of the method for wirelesscommunication described above with respect to the ninth set ofillustrative examples.

In a twelfth set of illustrative examples, another computer programproduct for communication by a wireless communications apparatus in awireless communications network is described. The computer programproduct may include a non-transitory computer-readable medium storingcomputer-executable code for wireless communications, the codeexecutable by a processor to dynamically select a configuration of anuplink channel for uplink communications in an unlicensed radiofrequency spectrum band, generate a waveform based on the selectedconfiguration, and communicate the generated waveform in a signal in theunlicensed radio frequency spectrum band using the uplink channel. Incertain examples, the code may also be executable by the processor toimplement one or more aspects of the method for wireless communicationdescribed above with respect to the ninth set of illustrative examples.

The foregoing has outlined rather broadly the features and technicaladvantages of examples according to the disclosure in order that thedetailed description that follows may be better understood. Additionalfeatures and advantages will be described hereinafter. The conceptionand specific examples disclosed may be readily utilized as a basis formodifying or designing other structures for carrying out the samepurposes of the present disclosure. Such equivalent constructions do notdepart from the spirit and scope of the appended claims. Features whichare believed to be characteristic of the concepts disclosed herein, bothas to their organization and method of operation, together withassociated advantages will be better understood from the followingdescription when considered in connection with the accompanying figures.Each of the figures is provided for the purpose of illustration anddescription only, and not as a definition of the limits of the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

A further understanding of the nature and advantages of the presentinvention may be realized by reference to the following drawings. In theappended figures, similar components or features may have the samereference label. Further, various components of the same type may bedistinguished by following the reference label by a dash and a secondlabel that distinguishes among the similar components. If only the firstreference label is used in the specification, the description isapplicable to any one of the similar components having the same firstreference label irrespective of the second reference label.

FIG. 1 shows a block diagram of a wireless communication system, inaccordance with various aspects of the present disclosure;

FIG. 2A shows a diagram that illustrates examples of deploymentscenarios for using LTE/LTE-A in an unlicensed radio frequency spectrumband, in accordance with various aspects of the present disclosure;

FIG. 2B shows a wireless communication system that illustrates anexample of a standalone mode for using LTE/LTE-A in an unlicensed radiofrequency spectrum band, in accordance with various aspects of thepresent disclosure;

FIG. 3 shows a first example of interference that may arise between theUEs and the base stations of a wireless communication system as the UEsand the base stations communicate in a common radio frequency spectrumband, in accordance with various aspects of the present disclosure;

FIG. 4 shows a second example of interference that may arise the UEs andthe base stations of a wireless communication system as the UEs and thebase stations communicate in a common radio frequency spectrum band, inaccordance with various aspects of the present disclosure;

FIG. 5 shows a downlink channel resource block in which a user equipmentreference signal (UE-RS) may be transmitted in a downlink channel, inaccordance with various aspects of the present disclosure;

FIG. 6 shows an uplink channel resource block for transmitting a DM-RSin an uplink channel, in accordance with various aspects of the presentdisclosure;

FIG. 7 shows another uplink channel resource block for transmitting aDM-RS in an uplink channel, in accordance with various aspects of thepresent disclosure;

FIG. 8A shows an example of how a PUCCH may be transmitted using aplurality of interleaved resource blocks, such as a first resourceblock, a second resource block, a third resource block, and a fourthresource block, in accordance with various aspects of the presentdisclosure;

FIG. 8B shows an example of PUCCH multiplexing within a plurality ofresource elements (e.g., first resource element, second resourceelement, and third resource element) of an enhanced resource elementgroup, in accordance with various aspects of the present disclosure;

FIG. 9 shows an example of frequency division multiplexing in thetransmission of a PUCCH and a PUSCH, in accordance with various aspectsof the present disclosure;

FIG. 10 shows another example of frequency division multiplexing in thetransmission of a PUCCH and a PUSCH, in accordance with various aspectsof the present disclosure;

FIG. 11 shows a block diagram of an apparatus for use in wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIG. 12 shows a block diagram of an apparatus for use in wirelesscommunication (e.g., to dynamically select a configuration of an uplinkchannel for uplink communications in an unlicensed radio frequencyspectrum band), in accordance with various aspects of the presentdisclosure;

FIG. 13 shows a block diagram of an apparatus for use in wirelesscommunication (e.g., to identify an OFDMA configuration of an uplinkchannel for uplink communications in an unlicensed radio frequencyspectrum band), in accordance with various aspects of the presentdisclosure;

FIG. 14 shows a block diagram of an apparatus for use in wirelesscommunication (e.g., to identify an OFDMA configuration of an uplinkchannel for uplink communications in an unlicensed radio frequencyspectrum band), in accordance with various aspects of the presentdisclosure;

FIG. 15 shows a block diagram of an apparatus for use in wirelesscommunication (e.g., to identify a set of common resource blocks fortransmission of a DM-RS in an uplink channel for uplink communicationsin an unlicensed radio frequency spectrum band), in accordance withvarious aspects of the present disclosure;

FIG. 16 shows a block diagram of an apparatus for use in wirelesscommunication (e.g., to identify a set of common resource blocks fortransmission of a DM-RS in an uplink channel for uplink communicationsin an unlicensed radio frequency spectrum band), in accordance withvarious aspects of the present disclosure;

FIG. 17 shows a block diagram of a base station for use in wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIG. 18 shows a block diagram of a UE for use in wireless communication,in accordance with various aspects of the present disclosure;

FIG. 19 is a flowchart illustrating an example of a method of wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIG. 20 is a flowchart illustrating an example of a method of wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIG. 21 is a flowchart illustrating an example of a method of wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIG. 22 is a flowchart illustrating an example of a method of wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIG. 23 is a flowchart illustrating an example of a method of wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIG. 24 is a flowchart illustrating an example of a method of wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIG. 25 is a flowchart illustrating an example of a method of wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIG. 26 is a flowchart illustrating an example of a method of wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIG. 27 is a flowchart illustrating an example of a method of wirelesscommunication, in accordance with various aspects of the presentdisclosure;

FIG. 28 is a flowchart illustrating an example of a method of wirelesscommunication, in accordance with various aspects of the presentdisclosure; and

FIG. 29 is a flowchart illustrating an example of a method of wirelesscommunication, in accordance with various aspects of the presentdisclosure.

DETAILED DESCRIPTION

When configuring an uplink channel for uplink communications (e.g.,LTE/LTE-A transmissions) in an unlicensed radio frequency spectrum band(e.g., a shared radio frequency spectrum band usable for Wi-Fi and/orLTE/LTE-A communications), it may be desirable to configure the uplinkchannel in different ways, depending on the nature of the uplinkcommunications, the potential for interference, and/or other factors. Asdisclosed herein, an uplink channel may be configured autonomously(e.g., by a UE), or in response to signaling received from a basestation, which signaling may indicate how the uplink channel needs to beconfigured or provide information from which a UE may determine how toconfigure the uplink channel. An uplink channel may also be configuredbased on a type or types of channel included in the uplink channel, suchas a PUSCH, a PUCCH, and/or a physical random access channel (PRACH). Anuplink channel may also be configured based on a potential forinterference and/or other factors.

In some examples, an uplink channel for LTE/LTE-A uplink communicationsin an unlicensed radio frequency spectrum band may be different from anuplink channel for LTE/LTE-A uplink communications in a licensed radiofrequency spectrum band, and there may be advantages to configuring theuplink channel for LTE/LTE-A uplink communications in the unlicensedradio frequency spectrum band differently than the uplink channel forLTE/LTE-A uplink communications in the licensed radio frequency spectrumband.

Techniques described herein may be used for various wirelesscommunications systems such as CDMA, TDMA, FDMA, OFDMA, SC-FDMA, andother systems. The terms “system” and “network” are often usedinterchangeably. A CDMA system may implement a radio technology such asCDMA2000, Universal Terrestrial Radio Access (UTRA), etc. CDMA2000covers IS-2000, IS-95, and IS-856 standards. IS-2000 Releases 0 and Aare commonly referred to as CDMA2000 1×, 1×, etc. IS-856 (TIA-856) iscommonly referred to as CDMA2000 1×EV-DO, High Rate Packet Data (HRPD),etc. UTRA includes Wideband CDMA (WCDMA) and other variants of CDMA. ATDMA system may implement a radio technology such as Global System forMobile Communications (GSM). An OFDMA system may implement a radiotechnology such as Ultra Mobile Broadband (UMB), Evolved UTRA (E-UTRA),IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802.20, Flash-OFDM™, etc.UTRA and E-UTRA are part of Universal Mobile Telecommunication System(UMTS). 3GPP Long Term Evolution (LTE) and LTE-Advanced (LTE-A) are newreleases of UMTS that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A, andGSM are described in documents from an organization named “3rdGeneration Partnership Project” (3GPP). CDMA2000 and UMB are describedin documents from an organization named “3rd Generation PartnershipProject 2” (3GPP2). The techniques described herein may be used for thesystems and radio technologies mentioned above as well as other systemsand radio technologies. The description below, however, describes an LTEsystem for purposes of example, and LTE terminology is used in much ofthe description below, although the techniques are applicable beyond LTEapplications.

The following description provides examples, and is not limiting of thescope, applicability, or configuration set forth in the claims. Changesmay be made in the function and arrangement of elements discussedwithout departing from the spirit and scope of the disclosure. Variousexamples may omit, substitute, or add various procedures or componentsas appropriate. For instance, the methods described may be performed inan order different from that described, and various steps may be added,omitted, or combined. Also, features described with respect to certainexamples may be combined in other examples.

FIG. 1 shows a block diagram of a wireless communication system 100, inaccordance with various aspects of the present disclosure. The wirelesscommunication system 100 includes a plurality of base stations 105(e.g., eNBs, WLAN access points, or other access points), a number ofuser equipments (UEs) 115, and a core network 130. Some of the basestations 105 may communicate with the UEs 115 under the control of abase station controller (not shown), which may be part of the corenetwork 130 or certain ones of the base stations 105 in variousexamples. Some of the base stations 105 may communicate controlinformation and/or user data with the core network 130 through backhaul132. In some examples, some of the base stations 105 may communicate,either directly or indirectly, with each other over backhaul links 134,which may be wired or wireless communication links. The wirelesscommunication system 100 may support operation on multiple carriers(waveform signals of different frequencies). Multi-carrier transmitterscan transmit modulated signals simultaneously on the multiple carriers.For example, each communication link 125 may be a multi-carrier signalmodulated according to various radio technologies. Each modulated signalmay be sent on a different carrier and may carry control information(e.g., reference signals, control channels, etc.), overhead information,data, etc.

The base stations 105 may wirelessly communicate with the UEs 115 viaone or more base station antennas. Each of the base stations 105 mayprovide communication coverage for a respective coverage area 110. Insome examples, a base station 105 may be referred to as an access point,a base transceiver station (BTS), a radio base station, a radiotransceiver, a basic service set (BSS), an extended service set (ESS), aNodeB, an evolved NodeB (eNB), a Home NodeB, a Home eNodeB, a WLANaccess point, a Wi-Fi node or some other suitable terminology. Thecoverage area 110 for a base station 105 may be divided into sectorsmaking up only a portion of the coverage area (not shown). The wirelesscommunication system 100 may include base stations 105 of differenttypes (e.g., macro, micro, and/or pico base stations). The base stations105 may also utilize different radio technologies, such as cellularand/or WLAN radio access technologies. The base stations 105 may beassociated with the same or different access networks or operatordeployments. The coverage areas of different base stations 105,including the coverage areas of the same or different types of basestations 105, utilizing the same or different radio technologies, and/orbelonging to the same or different access networks, may overlap.

In some examples, the wireless communication system 100 may include anLTE/LTE-A communication system (or network), which LTE/LTE-Acommunication system may support one or more modes of operation ordeployment in a licensed radio frequency spectrum band and/or anunlicensed radio frequency spectrum band. In other examples, thewireless communication system 100 may support wireless communicationusing access technology different from LTE/LTE-A. In LTE/LTE-Acommunication systems, the term evolved NodeB or eNB may be, forexample, used to describe the base stations 105.

The wireless communication system 100 may be or include a HeterogeneousLTE/LTE-A network in which different types of base stations 105 providecoverage for various geographical regions. For example, each basestation 105 may provide communication coverage for a macro cell, a picocell, a femto cell, and/or other type of cell. Small cells such as picocells, femto cells, and/or other types of cells may include low powernodes or LPNs. A macro cell, for example, covers a relatively largegeographic area (e.g., several kilometers in radius) and may allowunrestricted access by UEs with service subscriptions with the networkprovider. A pico cell would, for example, cover a relatively smallergeographic area and may allow unrestricted access by UEs with servicesubscriptions with the network provider. A femto cell would also, forexample, cover a relatively small geographic area (e.g., a home) and, inaddition to unrestricted access, may also provide restricted access byUEs having an association with the femto cell (e.g., UEs in a closedsubscriber group (CSG), UEs for users in the home, and the like). An eNBfor a macro cell may be referred to as a macro eNB. An eNB for a picocell may be referred to as a pico eNB. And, an eNB for a femto cell maybe referred to as a femto eNB or a home eNB. An eNB may support one ormultiple (e.g., two, three, four, and the like) cells.

The core network 130 may communicate with the base stations 105 via abackhaul 132 (e.g., S1 application protocol, etc.). The base stations105 may also communicate with one another, e.g., directly or indirectlyvia backhaul links 134 (e.g., X2 application protocol, etc.) and/or viabackhaul 132 (e.g., through core network 130). The wirelesscommunication system 100 may support synchronous or asynchronousoperation. For synchronous operation, the eNBs may have similar frameand/or gating timing, and transmissions from different eNBs may beapproximately aligned in time. For asynchronous operation, the eNBs mayhave different frame and/or gating timing, and transmissions fromdifferent eNBs may not be aligned in time. The techniques describedherein may be used for either synchronous or asynchronous operations.

The UEs 115 may be dispersed throughout the wireless communicationsystem 100, and each UE 115 may be stationary or mobile. A UE 115 mayalso be referred to by those skilled in the art as a mobile device, amobile station, a subscriber station, a mobile unit, a subscriber unit,a wireless unit, a remote unit, a wireless device, a wirelesscommunication device, a remote device, a mobile subscriber station, anaccess terminal, a mobile terminal, a wireless terminal, a remoteterminal, a handset, a user agent, a mobile client, a client, or someother suitable terminology. A UE 115 may be a cellular phone, a personaldigital assistant (PDA), a wireless modem, a wireless communicationdevice, a handheld device, a tablet computer, a laptop computer, acordless phone, a wearable item such as a watch or glasses, a wirelesslocal loop (WLL) station, or the like. A UE 115 may be able tocommunicate with macro eNBs, pico eNBs, femto eNBs, relays, and thelike. A UE 115 may also be able to communicate over different types ofaccess networks, such as cellular or other WWAN access networks, or WLANaccess networks.

The communication links 125 shown in wireless communication system 100may include uplink channels for carrying uplink (UL) communications(e.g., transmissions from a UE 115 to a base station 105) and/ordownlink channels for carrying downlink (DL) communications (e.g.,transmissions from a base station 105 to a UE 115). The ULcommunications or transmissions may also be called reverse linkcommunications or transmissions, while the DL communications ortransmissions may also be called forward link communications ortransmissions. The downlink communications or transmissions may be madeusing a licensed radio frequency spectrum band, an unlicensed radiofrequency spectrum band, or both. Similarly, the uplink communicationsor transmissions may be made using a licensed radio frequency spectrumband, an unlicensed radio frequency spectrum band, or both.

In some examples of the wireless communication system 100, variousdeployment scenarios for LTE/LTE-A in an unlicensed radio frequencyspectrum band may be supported, including a supplemental downlink modein which LTE/LTE-A downlink communications in a licensed radio frequencyspectrum band may be offloaded to an unlicensed radio frequency spectrumband, a carrier aggregation mode in which both LTE/LTE-A downlink anduplink communications may be offloaded from a licensed radio frequencyspectrum band to an unlicensed radio frequency spectrum band, and astandalone mode in which LTE/LTE-A downlink and uplink communicationsbetween a base station (e.g., eNB) and a UE may take place in anunlicensed radio frequency spectrum band. Base stations 105 as well asUEs 115 may support one or more of these or similar modes of operation.OFDMA waveforms may be used in the communication links 125 for LTE/LTE-Adownlink communications in a licensed and/or an unlicensed radiofrequency spectrum band, while OFDMA, SC-FDMA and/or RB interleaved FDMAwaveforms may be used in the communication links 125 for LTE/LTE-Auplink communications in a licensed and/or an unlicensed radio frequencyspectrum band.

FIG. 2A shows a diagram that illustrates examples of deploymentscenarios for using LTE/LTE-A in an unlicensed radio frequency spectrumband, in accordance with various aspects of the present disclosure. Inone example, FIG. 2A illustrates a wireless communication system 200illustrating examples of a supplemental downlink mode and a carrieraggregation mode for an LTE/LTE-A network that supports deployment inunlicensed radio frequency spectrum band. The wireless communicationsystem 200 may be an example of portions of the wireless communicationsystem 100 of FIG. 1. Moreover, the base station 205 may be an exampleof aspects of one or more of the base stations 105 of FIG. 1, while theUEs 215, 215-a, and 215-b may be examples of aspects of one or more ofthe UEs 115 of FIG. 1.

In the example of a supplemental downlink mode in the wirelesscommunication system 200, the base station 205 may transmit OFDMAwaveforms to a UE 215 using a downlink channel 220. The downlink channel220 may be associated with a frequency F1 in an unlicensed radiofrequency spectrum band. The base station 205 may transmit OFDMAwaveforms to the same UE 215 using a first bidirectional link 225 andmay receive SC-FDMA waveforms from that UE 215 using the firstbidirectional link 225. The first bidirectional link 225 may beassociated with a frequency F4 in a licensed radio frequency spectrumband. The downlink channel 220 in the unlicensed radio frequencyspectrum band and the first bidirectional link 225 in the licensed radiofrequency spectrum band may operate concurrently. The downlink channel220 may provide a downlink capacity offload for the base station 205. Insome examples, the downlink channel 220 may be used for unicast services(e.g., addressed to one UE) or for multicast services (e.g., addressedto several UEs). This scenario may occur with any service provider(e.g., a traditional mobile network operator (MNO)) that uses a licensedradio frequency spectrum band and needs to relieve some of the trafficand/or signaling congestion.

In one example of a carrier aggregation mode in the wirelesscommunication system 200, the base station 205 may transmit OFDMAwaveforms to a UE 215-a using a second bidirectional link 230 and mayreceive OFDMA waveforms, SC-FDMA waveforms, and/or RB interleaved FDMAwaveforms from the same UE 215-a using the second bidirectional link230. The second bidirectional link 230 may be associated with thefrequency F1 in the unlicensed radio frequency spectrum band. The basestation 205 may also transmit OFDMA waveforms to the same UE 215-a usinga third bidirectional link 235 and may receive SC-FDMA waveforms fromthe same UE 215-a using the third bidirectional link 235. The thirdbidirectional link 235 may be associated with a frequency F2 in alicensed radio frequency spectrum band. The second bidirectional link230 may provide a downlink and uplink capacity offload for the basestation 205. Like the supplemental downlink mode described above, thisscenario may occur with any service provider (e.g., MNO) that uses alicensed radio frequency spectrum band and needs to relieve some of thetraffic and/or signaling congestion.

In another example of a carrier aggregation mode in the wirelesscommunication system 200, the base station 205 may transmit OFDMAwaveforms to a UE 215-b using a fourth bidirectional link 240 and mayreceive OFDMA waveforms, SC-FDMA waveforms, and/or RB interleavedwaveforms from the same UE 215-b using the fourth bidirectional link240. The fourth bidirectional link 240 may be associated with afrequency F3 in an unlicensed radio frequency spectrum band. The basestation 205 may also transmit OFDMA waveforms to the same UE 215-b usinga fifth bidirectional link 245 and may receive SC-FDMA waveforms fromthe same UE 215-b using the fifth bidirectional link 245. The fifthbidirectional link 245 may be associated with the frequency F2 in thelicensed radio frequency spectrum band. The fourth bidirectional link240 may provide a downlink and uplink capacity offload for the basestation 205. This example and those provided above are presented forillustrative purposes and there may be other similar modes of operationor deployment scenarios that combine LTE/LTE-A in licensed andunlicensed radio frequency spectrum bands for capacity offload.

As described above, the typical service provider that may benefit fromthe capacity offload offered by using LTE/LTE-A in an unlicensed radiofrequency spectrum band is a traditional MNO having access rights to anLTE/LTE-A radio frequency spectrum band. For these service providers, anoperational configuration may include a bootstrapped mode (e.g.,supplemental downlink, carrier aggregation) that uses the LTE/LTE-Aprimary component carrier (PCC) on the licensed radio frequency spectrumband and a secondary component carrier (SCC) on the unlicensed radiofrequency spectrum band.

In the carrier aggregation mode, data and control may, for example, becommunicated in the licensed radio frequency spectrum band (e.g., viafirst bidirectional link 225, third bidirectional link 235, and fifthbidirectional link 245) while data may, for example, be communicated inthe unlicensed radio frequency spectrum band (e.g., via secondbidirectional link 230 and fourth bidirectional link 240). The carrieraggregation mechanisms supported when using an unlicensed radiofrequency spectrum band may fall under a hybrid frequency divisionduplexing-time division duplexing (FDD-TDD) carrier aggregation or aTDD-TDD carrier aggregation with different symmetry across componentcarriers.

FIG. 2B shows a wireless communication system 250 that illustrates anexample of a standalone mode for using LTE/LTE-A in an unlicensed radiofrequency spectrum band, in accordance with various aspects of thepresent disclosure. The wireless communication system 250 may be anexample of portions of the wireless communication system 100 and/or 200described with reference to FIGS. 1 and/or 2A. Moreover, the basestation 205 may be an example of aspects of one or more of the basestations 105 and/or 205 described with reference to FIGS. 1 and/or 2A,while the UE 215-c may be an example of aspects of one or more of theUEs 115 and/or 215 described with reference to FIGS. 1 and/or 2A.

In the example of a standalone mode in the wireless communication system250, the base station 205 may transmit OFDMA waveforms to the UE 215-cusing a bidirectional link 255 and may receive OFDMA waveforms, SC-FDMAwaveforms, and/or RB interleaved FDMA waveforms from the UE 215-c usingthe bidirectional link 255. The bidirectional link 255 may be associatedwith the frequency F3 in the unlicensed radio frequency spectrum banddescribed with reference to FIG. 2A. The standalone mode may be used innon-traditional wireless access scenarios, such as in-stadium access(e.g., unicast, multicast). The typical service provider for this modeof operation may be a stadium owner, cable company, event host, hotel,enterprise, or large corporation that does not have access to a licensedradio frequency spectrum band.

In some examples, a transmitting device such as a base station 105, 205(e.g., an eNB) described with reference to FIGS. 1, 2A, and/or 2B, or aUE 115 and/or 215 described with reference to FIGS. 1, 2A, and/or 2B,may use a gating interval to gain access to a channel of the unlicensedradio frequency spectrum band. The gating interval may define theapplication of a contention-based protocol, such as a Listen Before Talk(LBT) protocol based on the LBT protocol specified in ETSI (EN 301 893).When using a gating interval that defines the application of an LBTprotocol, the gating interval may indicate when a transmitting apparatusneeds to perform a Clear Channel Assessment (CCA). The outcome of theCCA may indicate to the transmitting apparatus whether a channel of theunlicensed radio frequency spectrum band is available or in use. Whenthe CCA indicates that the channel is available (e.g., “clear” for use),the gating interval may allow the transmitting apparatus to use thechannel—typically for a predefined transmission interval. When the CCAindicates that the channel is not available (e.g., in use or reserved),the gating interval may prevent the transmitting apparatus from usingthe channel during the transmission interval.

In some examples, it may be useful for a transmitting apparatus togenerate a gating interval on a periodic basis and synchronize at leastone boundary of the gating interval with at least one boundary of aperiodic frame structure. For example, it may be useful to generate aperiodic gating interval for a cellular downlink in a licensed radiofrequency spectrum band, and to synchronize at least one boundary of theperiodic gating interval with at least one boundary of a periodic framestructure (e.g., an LTE/LTE-A radio frame) associated with the cellulardownlink.

Under some scenarios, wireless communications (e.g., transmissions)received by a UE or a base station (e.g., an eNB) may be associated withinterference. In this regard, FIG. 3 shows a first example ofinterference that may arise between the UEs and the base stations of awireless communication system 300 as the UEs and the base stationscommunicate in a common radio frequency spectrum band, in accordancewith various aspects of the present disclosure. In some examples, thewireless communication system 300 may be an example of one or moreaspects of the wireless communication system 100, 200, and/or 250described with reference to FIGS. 1, 2A, and/or 2B.

By way of example, FIG. 3 shows a first base station 305-a, a secondbase station 305-b, a first UE 315-a, and a second UE 315-b. When one ofthe UEs (e.g., the first UE 315-a) receives a first transmission 325from one of the eNBs (e.g., the first base station 305-a), the firsttransmission 325 may be associated with second interference 340 as aresult of another UE (e.g., the second UE 315-b) making a secondtransmission 330 to another eNB (e.g., the second base station 305-b).Similarly, when one of the base stations (e.g., the second base station305-b) receives the second transmission 330 from one of the UEs (e.g.,the second UE 315-b), the second transmission 330 may be associated withfirst interference 335 as a result of another base station (e.g., thefirst base station 305-a) making the first transmission 325 to anotherUE (e.g., the first UE 315-a). Without coordination between the first UE315-a, the second UE 315-b, the first base station 305-a, and the secondbase station 305-b, the receivers at the first UE 315-a, the second UE315-b, the first base station 305-a, and the second base station 305-bmay only be able to blindly estimate the nature of interference such asthe first interference 335 and/or the second interference 340. A blindestimate of interference may not be sufficient to enable cancelation ofthe interference.

FIG. 4 shows a second example of interference that may arise between theUEs and the base stations of a wireless communication system 400 as theUEs and the base stations communicate in a common radio frequencyspectrum band, in accordance with various aspects of the presentdisclosure.

By way of example, FIG. 4 shows a first base station 405-a, a secondbase station 405-b, a first UE 415-a, and a second UE 415-b. When one ofthe UEs (e.g., the first UE 415-a) receives a first transmission 425from one of the base stations (e.g., the first base station 405-a), thefirst transmission 425 may be associated with first interference 435 asa result of another base station (e.g., the second base station 405-b)making a second transmission 430 to another UE (e.g., the second UE415-b). Similarly, when the second UE 415-b receives the secondtransmission 430 from the second base station 405-b, the secondtransmission 430 may be associated with second interference 440 as aresult of the first transmission 425 from the first base station 405-ato the first UE 415-a. Without coordination between the first UE 415-a,the second UE 415-b, the first base station 405-a, and the second basestation 405-b, the receivers at the first UE 415-a, the second UE 415-b,the first base station 405-a, and the second base station 405-b may onlybe able to blindly estimate the nature of interference such as the firstinterference 435 and/or the second interference 440. A blind estimate ofinterference may not be sufficient to enable cancelation of theinterference.

To facilitate cancelation of interference under scenarios such as thosedescribed with reference to FIGS. 4 and/or 5, the base stations withoverlapping coverage areas may be assigned (or may negotiate) a commonvirtual cell identifier (i.e., Virtual Cell ID). The base stations, andthe UEs with which they communicate, may then associate the commonvirtual cell identifier with their transmissions (e.g., the basestations may associate the common virtual cell identifier with downlinktransmissions from the base stations to the UEs, and the UEs mayassociate the common virtual cell identifier with uplink transmissionsfrom the UEs to the base stations).

A port associated with a first spatial multiplexing may be identifiedfor transmission of a DM-RS between one base station (e.g., first basestation 305-a or 405-a described with reference to FIG. 3 or 4) and oneor more UEs (e.g., the first UE 315-a or 415-a), and a port associatedwith a second spatial multiplexing may be identified for transmission ofa DM-RS between another base station (e.g., second base station 305-b or405-b) and one or more UEs (e.g., second UE 315-b or 415-b). This mayimprove the ability of a base station (e.g., first base station 305-a/405-a or second base station 305-b/ 405-b) or UE (e.g., first UE 315-a/415-a or second UE 315-b/ 415-b) to cancel interference from a receivedtransmission. Improved interference cancelation may improve channelestimation and/or other aspects of a wireless communication system.

When the base stations shown in FIGS. 3 and/or 4 are assigned the samevirtual cell identifier, the DM-RS generated by the base stations andUEs may be the same, which may also enable improved interferencecancelation.

In some examples, different link identifiers may be assigned to anuplink channel and a downlink channel, such that the different linkidentifiers may be associated with respective transmissions in theuplink channel and the downlink channel. For example, with reference tothe first base station 305-a/ 405-a and the first UE 315-a/ 415-a inFIGS. 3 and/or 4, a first link identifier may be associated with theuplink channel between the first base station 305-a/ 405-a and the firstUE 315-a/ 415-a, and a second link identifier may be associated with thedownlink channel between the second base station 305-b/ 405-b and thesecond UE 315-b/ 415-b, wherein the first link identifier is differentfrom the second link identifier. In some examples, transmitting thefirst link identifier with transmissions in the uplink channel mayinclude generating a DM-RS as a function of the first link identifier.Similarly, transmitting the second link identifier with transmissions inthe uplink channel may include generating a DM-RS as a function of thesecond link identifier. By assigning a link identifier to eachtransmission, a receiver may determine whether interference is a resultof an uplink transmission or a downlink transmission. An uplinktransmission may include an SRS and a PUCCH structure, whereas adownlink transmission may include a CRS and have configured channelstate information reference signal (CSI-RS) processes. This knowledgemay also be used to improve interference cancelation.

FIG. 5 shows a downlink channel resource block 500 in which a userequipment reference signal (UE-RS) may be transmitted in a downlinkchannel, in accordance with various aspects of the present disclosure.The term UE-RS may, in some examples, be used to distinguish a DM-RStransmitted in a downlink channel from a DM-RS transmitted in an uplinkchannel.

The downlink channel resource block 500 includes a plurality of resourceelements (e.g., first resource element 505 and second resource element510). Each resource element may correspond to one of a number of timeslots (e.g., OFDM symbol positions 515) and one of a number of frequencysub-carriers 520. By way of example, the downlink channel resource block500 includes resource elements spanning fourteen OFDM symbol positions(or two slots, labeled Slot 0 and Slot 1; or one Subframe) and twelvefrequency sub-carriers.

By way of further example, a UE-RS 525 may be transmitted in a set ofone or more time slots and one or more frequency sub-carriers of thedownlink channel resource block 500, such as, in the resource elementsfound at the intersections of frequency sub-carriers 0, 5, and 10 andOFDM symbol positions 5 and 6 in each of Slot 0 and Slot 1. In someexamples, a common reference signal (CRS) may be transmitted in thedownlink channel resource block 500 (e.g., when the downlink channelresource block 500 is in a subframe 0 or a subframe 5 of a frame (notshown)). In some examples, CSI-RS processes may be included in thedownlink channel resource block 500.

FIG. 6 shows an uplink channel resource block 600 for transmitting aDM-RS in an uplink channel, in accordance with various aspects of thepresent disclosure.

The uplink channel resource block 600 may be structured similarly to thedownlink channel resource block 500 described with reference to FIG. 5,and may include a plurality of resource elements (e.g., first resourceelement 605 and second resource element 610). Each resource element maycorrespond to one of a number of time slots (e.g., OFDM symbol positions615) and one of a number of frequency sub-carriers 620. By way ofexample, the uplink channel resource block 600 includes resourceelements spanning fourteen OFDM symbol positions (or two slots, labeledSlot 0 and Slot 1; or one Subframe) and twelve frequency sub-carriers.

By way of further example, a DM-RS 625 may be transmitted in a set ofone or more time slots and one or more frequency sub-carriers of theuplink channel resource block 600, such as, in the resource elementsfound at the intersections of frequency sub-carriers 0, 5, and 10 andOFDM symbol positions 5 and 6 in each of Slot 0 and Slot 1. In thismanner, a common set of resource blocks may be identified fortransmission of a DM-RS in an uplink channel and a UE-RS in a downlinkchannel between a base station and a UE that are communicating with oneanother. This may improve the ability of the base station and UE tocancel interference. Also, the uplink and downlink waveforms may be madeorthogonal in their UE-RS/DM-RS portion.

Because the DM-RS 625 shown in FIG. 6 occupies certain frequencysub-carriers in the last OFDM symbol position of the subframe, asounding reference signal (SRS) 630 may be located in an OFDM symbolposition other than the last OFDM symbol position. In FIG. 6, an SRS 630is located in the first OFDM symbol position of the subframe. In otherexamples, an SRS may be located in a different OFDM symbol position.

FIG. 7 shows another uplink channel resource block 700 for transmittinga DM-RS in an uplink channel, in accordance with various aspects of thepresent disclosure.

The uplink channel resource block 700 may be structured similarly to thedownlink channel resource block 500 described with reference to FIG. 5,and may include a plurality of resource elements (e.g., first resourceelement 705 and second resource element 710). Each resource element maycorrespond to one of a number of time slots (e.g., OFDM symbol positions715) and one of a number of frequency sub-carriers 720. By way ofexample, the uplink channel resource block 700 includes resourceelements spanning fourteen OFDM symbol positions (or two slots, labeledSlot 0 and Slot 1; or one Subframe) and twelve frequency sub-carriers.

By way of further example, a DM-RS 725 may be transmitted in a set ofone or more time slots and one or more frequency sub-carriers of theuplink channel resource block 700, such as, in the resource elementsfound at the intersections of frequency sub-carriers 0, 5, and 10 andOFDM symbol positions 4 and 5 in each of Slot 0 and Slot 1. In thismanner, and in comparison to the downlink channel resource block 500described with reference to FIG. 5, a non-colliding set of resourceblocks may be identified for transmission of a DM-RS 725 in an uplinkchannel and a UE-RS 525 in a downlink channel, between a base stationand a UE that are communicating with one another. This may enable an SRS730 to be located in the last OFDM symbol position of the uplink channelresource block 700, similarly to where an SRS is located in an uplinkchannel for LTE/LTE-A uplink communications in a licensed radiofrequency spectrum band. In other examples, an SRS may be located in adifferent OFDM symbol position. Also, the uplink and downlink waveformsmay be made orthogonal in their UE-RS/DM-RS portion.

Turning now to the transmission of a PUCCH and/or a PUSCH, a PUCCHtransmission in a conventional LTE/LTE-A communication may only occupyone resource block. However, there may be a requirement that certaincommunications (e.g., LTE/LTE-A communications in an unlicensed radiofrequency spectrum band) occupy at least a certain percentage of theavailable frequency bandwidth (e.g., at least 80% of the availablefrequency bandwidth).

In this regard, FIG. 8A shows an example 800 of how a PUCCH may betransmitted using a plurality of interleaved resource blocks, such as afirst resource block 805, a second resource block 810, a third resourceblock 815, and a fourth resource block 820, in accordance with variousaspects of the present disclosure. The first resource block 805, thesecond resource block 810, the third resource block 815, and the fourthresource block 820 may span a certain percentage of the availablefrequency bandwidth 825 of a subframe 830, so that transmissions usingthe first resource block 805, the second resource block 810, the thirdresource block 815, and the fourth resource block 820 occupy at leastthe required percentage of the frequency bandwidth. In one example,duplicate copies of the PUCCH may be transmitted in each of the firstresource block 805, the second resource block 810, the third resourceblock 815, and the fourth resource block 820. In some examples,different subsets of symbols (not shown) in the first resource block805, the second resource block 810, the third resource block 815, andthe fourth resource block 820 may be allocated for PUCCH transmissionsof different UEs. In another example, a PUCCH may be multiplexed withinthe first resource block 805, the second resource block 810, the thirdresource block 815, and the fourth resource block 820 according to acode division multiplexing sequence or other orthogonal sequence.

FIG. 8B shows an example 850 of PUCCH multiplexing within a plurality ofresource elements (e.g., first resource element 885, second resourceelement 890, and third resource element 895) of an enhanced resourceelement group, in accordance with various aspects of the presentdisclosure. The enhanced resource element group may be distributedacross a plurality of interleaved resource blocks, such as a firstresource block 855, a second resource block 860, a third resource block865, and a fourth resource block 870 that span a certain percentage ofthe available frequency bandwidth 875 of a subframe 880.

By way of example, FIG. 8B shows two resource element groups (e.g.,Resource Element Group 1 and Resource Element Group 2). The differentresource element groups may be associated with different UEs (e.g., aUE1 and a UE2). The resource element groups may be multiplexed withinthe first resource block 855, the second resource block 860, the thirdresource block 865, and the fourth resource block 870.

FIG. 9 shows an example 900 of frequency division multiplexing in thetransmission of a PUCCH and a PUSCH, in accordance with various aspectsof the present disclosure. FIG. 9 shows three different sets of resourceblocks, a first set of resource blocks 905, a second set of resourceblocks 910, and a third set of resource blocks 915. Each set of resourceblocks may represent the frequency bandwidth of a particular subframe,such as a first subframe 955, a second subframe 960, and a thirdsubframe 965. In some examples, the frequency division multiplexingtransmission of the PUCCH and the PUSCH may span at least a certainpercentage, including all, of the available frequency bandwidth of aparticular subframe.

In the first set of resource blocks 905 representing a frequencybandwidth of the first subframe 955, an uplink channel to be transmittedmay include a PUCCH. In such a scenario, a first subset of resourceblocks of the first set of resource blocks 905 may be used to transmitthe uplink channel. The first subset of resource blocks may include aplurality of interleaved resource blocks, such as a first resource block920, a second resource block 925, a third resource block 930, and afourth resource block 935. One or more UEs may transmit during each ofthe interleaved resource blocks.

In the second set of resource blocks 910 representing a frequencybandwidth of the second subframe 960, an uplink channel to betransmitted may include a PUSCH. In such a scenario, a second subset ofresource blocks of the second set of resource blocks 910 may be used totransmit the uplink channel. The second subset of resource blocks mayinclude a plurality of interleaved resource blocks (including a firstgroup of resource blocks 940, a second group of resource blocks 945, anda third group of resource blocks 950).

In the third set of resource blocks 915 representing a frequencybandwidth of the third subframe 965, an uplink channel to be transmittedmay include a PUCCH and a PUSCH. In such a scenario, the PUCCH and thePUSCH may be frequency division multiplexed, using the first subset ofresource blocks including the first resource block 920, the secondresource block 925, the third resource block 930, and the fourthresource block 935 to transmit the PUCCH and the second subset ofresource blocks (including the first group of resource blocks 940, thesecond group of resource blocks 945, and the third group of resourceblocks 950) to transmit the PUSCH.

FIG. 10 shows another example 1000 of frequency division multiplexing inthe transmission of a PUCCH and a PUSCH, in accordance with variousaspects of the present disclosure. FIG. 10 shows three different sets ofresource blocks. For example, a first set of resource blocks 1005, asecond set of resource blocks 1010, and a third set of resource blocks1015. Each set of resource blocks may represent the frequency bandwidthof a particular subframe. For example, the first set of resource blocks1005 may represent the frequency bandwidth of a first subframe 1055, thesecond set of resource blocks 1010 may represent the frequency bandwidthof a second subframe 1060, and the third set of resource blocks 1015 mayrepresent the frequency bandwidth of a third subframe 1065. In someexamples, the frequency division multiplexing transmission of the PUCCHand the PUSCH may span at least a certain percentage, including all, ofthe available frequency bandwidth of a particular subframe.

In the first set of resource blocks 1005 representing a frequencybandwidth of the first subframe 1055, an uplink channel to betransmitted may include a PUCCH. In such a scenario, a first subset ofresource blocks of the first set of resource blocks 1005 may be used totransmit the uplink channel. The first subset of resource blocks mayinclude a plurality of interleaved resource blocks, such as a firstresource block 1020, a second resource block 1025, a third resourceblock 1030, and a fourth resource block 1035.

In the second set of resource blocks 1010 representing a frequencybandwidth of the second subframe 1060, an uplink channel to betransmitted may include a PUSCH. In such a scenario, a second subset ofresource blocks of the first set of resource blocks may be used totransmit the uplink channel. The second subset of resource blocks mayinclude a plurality of interleaved resource blocks (including a firstgroup of resource blocks 1040, a second group of resource blocks 1045,and a third group of resource blocks 1050).

In the third set of resource blocks 1015 representing a frequencybandwidth of the third subframe 1065, an uplink channel to betransmitted may include a PUCCH and a PUSCH. In such a scenario, thePUCCH and the PUSCH may be frequency division multiplexed. Whenfrequency division multiplexing the PUCCH and the PUSCH on the uplinkchannel, a number of resource blocks assigned for PUCCH may be differentfrom a number of resource blocks assigned for PUCCH when the PUCCH andPUSCH are not frequency division multiplexed on the uplink channel(e.g., for a standalone PUCCH transmission on the uplink channel). Forexample, a subset (e.g., less than all) of the first set of resourceblocks (e.g., first resource block 1020 and fourth resource block 1035)may be used to transmit the PUCCH, and the resource blocks of the firstset of resource blocks 1005 that are not used to transmit the PUCCH(e.g., second resource block 1025 and third resource block 1030) may beused to transmit the PUSCH. In another example, the resource blocks ofthe first set of resource blocks 1005 that are not used to transmit thePUCCH (e.g., second resource block 1025 and third resource block 1030)may be used to transmit a PUCCH or a PUSCH of a different UE. The firstresource block 1020 and the fourth resource block 1035 of the first setused to transmit the PUCCH may, in some examples, be selected such thatthey span at least a certain percentage of the available resourceblocks.

In another example of frequency division multiplexing the transmissionof a PUCCH and a PUSCH, the PUCCH and the PUSCH may be frequencydivision multiplexed by puncturing at least one frequency sub-carrier ofat least one resource block of the first set of resource blocks 1005, totransmit at least part of the PUSCH. For example, a resource blockassigned to transmit PUCCH may have a narrower sub-carrier frequencybandwidth or shorter time period than a resource block (e.g., the firstset of resource blocks 1005) assigned to transmit PUCCH when the PUCCHand PUSCH are not frequency division multiplexed on the uplink channel(e.g., a standalone PUCCH transmission on the uplink channel).

In another example of frequency division multiplexing the transmissionof a PUCCH and a PUSCH, some resources assigned to PUCCH may overlapwith resources assigned to PUSCH. When resources assigned to PUCCH thatoverlap with resources assigned to PUSCH are not used, the resourcesassigned to the PUCCH that overlap with resources assigned to PUSCH maybe used to transmit PUSCH.

FIG. 11 shows a block diagram 1100 of an apparatus 1115 for use inwireless communication, in accordance with various aspects of thepresent disclosure. In some examples, the apparatus 1115 may be anexample of aspects of one or more of the UEs 115, 215, and/or 1815described with reference to FIGS. 1, 2A, 2B, and/or 18, aspects of oneor more of the base stations 105, 205, and/or 1705 described withreference to FIGS. 1, 2A, 2B, and/or 17, and/or aspects of one or moreof the apparatuses 1215, 1315, 1415, 1515, and/or 1615 described withreference to FIGS. 12, 13, 14, 15, and/or 16. The apparatus 1115 mayalso be a processor. The apparatus 1115 may include a receiver module1110, a wireless communication management module 1120, and/or atransmitter module 1130. Each of these components may be incommunication with each other.

The components of the apparatus 1115 may, individually or collectively,be implemented using one or more application-specific integratedcircuits (ASICs) adapted to perform some or all of the applicablefunctions in hardware. Alternatively, the functions may be performed byone or more other processing units (or cores), on one or more integratedcircuits. In other examples, other types of integrated circuits may beused (e.g., Structured/Platform ASICs, Field Programmable Gate Arrays(FPGAs), and other Semi-Custom ICs), which may be programmed in anymanner known in the art. The functions of each unit may also beimplemented, in whole or in part, with instructions embodied in amemory, formatted to be executed by one or more general orapplication-specific processors.

In some examples, the receiver module 1110 may be or include a radiofrequency (RF) receiver, such as an RF receiver operable to receivetransmissions in a first radio frequency spectrum band (e.g., a licensedradio frequency spectrum band, such as a radio frequency spectrum bandusable for LTE/LTE-A communications) and/or a second radio frequencyspectrum band (e.g., an unlicensed radio frequency spectrum band, suchas a shared radio frequency spectrum band usable for Wi-Fi and/orLTE/LTE-A communications). The receiver module 1110 may be used toreceive various types of data and/or control signals (i.e.,transmissions) over one or more communication links of a wirelesscommunication system including the first and second radio frequencyspectrum bands, such as one or more communication links of the wirelesscommunication system 100, 200, and/or 250 described with reference toFIGS. 1, 2A, and/or 2B.

In some examples, the transmitter module 1130 may be or include an RFtransmitter, such as an RF transmitter operable to transmit in the firstradio frequency spectrum band and/or the second radio frequency spectrumband. The transmitter module 1130 may be used to transmit various typesof data and/or control signals (i.e., transmissions) over one or morecommunication links of the wireless communication system including thefirst radio frequency spectrum band and the second radio frequencyspectrum band.

In some examples, the wireless communication management module 1120 maymanage the receipt of wireless communications via the receiver module1110 and/or the transmission of wireless communications via thetransmitter module 1130.

FIG. 12 shows a block diagram 1200 of an apparatus 1215 for use inwireless communication (e.g., to dynamically select a configuration ofan uplink channel for uplink communications in an unlicensed radiofrequency spectrum band), in accordance with various aspects of thepresent disclosure. In some examples, the apparatus 1215 may be anexample of aspects of one or more of the UEs 115, 215, and/or 1815described with reference to FIGS. 1, 2A, 2B, and/or 18, and/or aspectsof one or more of the apparatuses 1115, 1315, 1415, 1515, and/or 1615described with reference to FIGS. 11, 13, 14, 15, and/or 16. Theapparatus 1215 may also be a processor. The apparatus 1215 may include areceiver module 1210, a wireless communication management module 1220,and/or a transmitter module 1230. Each of these components may be incommunication with each other.

The components of the apparatus 1215 may, individually or collectively,be implemented using one or more ASICs adapted to perform some or all ofthe applicable functions in hardware. Alternatively, the functions maybe performed by one or more other processing units (or cores), on one ormore integrated circuits. In other examples, other types of integratedcircuits may be used (e.g., Structured/Platform ASICs, FPGAs, and otherSemi-Custom ICs), which may be programmed in any manner known in theart. The functions of each unit may also be implemented, in whole or inpart, with instructions embodied in a memory, formatted to be executedby one or more general or application-specific processors.

In some examples, the receiver module 1210 may be or include a radiofrequency (RF) receiver, such as an RF receiver operable to receivetransmissions in a first radio frequency spectrum band (e.g., a licensedradio frequency spectrum band usable for LTE/LTE-A communications)and/or a second radio frequency spectrum band (e.g., an unlicensed radiofrequency spectrum band, such as a shared radio frequency spectrum bandusable for Wi-Fi and/or LTE/LTE-A communications). The RF receiver mayinclude separate receivers for the first radio frequency spectrum bandand the second radio frequency spectrum band. The separate receiversmay, in some examples, take the form of a licensed radio frequencyspectrum band receiver module 1212 for communicating over the firstradio frequency spectrum band, and an unlicensed radio frequencyspectrum band receiver module 1214 for communicating over the secondradio frequency spectrum band. The receiver module 1210, including thelicensed radio frequency spectrum band receiver module 1212 and/or theunlicensed radio frequency spectrum band receiver module 1214, may beused to receive various types of data and/or control signals (i.e.,transmissions) over one or more communication links of a wirelesscommunication system including the first and second radio frequencyspectrum bands, such as one or more communication links of the wirelesscommunication system 100, 200, and/or 250 described with reference toFIGS. 1, 2A, and/or 2B.

In some examples, the transmitter module 1230 may be or include an RFtransmitter, such as an RF transmitter operable to transmit in the firstradio frequency spectrum band and/or the second radio frequency spectrumband. The RF transmitter may include separate transmitters for the firstradio frequency spectrum band and the second radio frequency spectrumband. The separate transmitters may, in some examples, take the form ofa licensed radio frequency spectrum band transmitter module 1232 forcommunicating over the first radio frequency spectrum band, and anunlicensed radio frequency spectrum band transmitter module 1234 forcommunicating over the second radio frequency spectrum band. Thetransmitter module 1230, including the licensed radio frequency spectrumband transmitter module 1232 and/or the unlicensed radio frequencyspectrum band transmitter module 1234, may be used to transmit varioustypes of data and/or control signals (i.e., transmissions) over one ormore communication links of the wireless communication system includingthe first radio frequency spectrum band and the second radio frequencyspectrum band.

In some examples, the wireless communication management module 1220 maybe an example of one or more aspects of the wireless communicationmanagement module 1120 described with reference to FIG. 11 and mayinclude a uplink channel configuration selector module 1240, a waveformgenerator module 1245, and/or a waveform communication module 1250. Eachof these components may be in communication with each other.

In some examples, the uplink channel configuration selector module 1240may be used to dynamically select a configuration of an uplink channelfor uplink communications (e.g., LTE/LTE-A uplink communications) in anunlicensed radio frequency spectrum band. In some examples, theconfiguration of the uplink channel may be selected from among an OFDMAconfiguration, an SC-FDMA configuration, and/or an RB interleaved FDMAconfiguration.

In some examples, the uplink channel configuration selector module 1240may select the configuration of the uplink channel based at least inpart on signaling received from a base station (e.g., an eNB). Thesignaling may, in some examples, indicate an RB allocation. In someexamples, the signaling may be received over a downlink channel in thelicensed radio frequency spectrum band (e.g., via the licensed radiofrequency spectrum band receiver module 1212) or over a downlink channelin the unlicensed radio frequency spectrum band (e.g., via theunlicensed radio frequency spectrum band receiver module 1214). In someexamples, the signaling may include Layer 1 signaling (e.g., ePDCCH orPDCCH based signaling) and/or Layer 2 signaling (e.g., MAC header basedsignaling). The signaling may, in some examples, ask a UE or apparatusperforming the method 2000 to dynamically or semi-statically select aconfiguration of the uplink channel based at least in part on thereceived signaling.

In other cases, the uplink channel configuration selector module 1240may select the configuration of the uplink channel based on theproximity of the apparatus 1215 to a base station. For example, an RBlevel interleaved FDMA configuration or an OFDMA configuration may beselected when the apparatus 1215 is relatively closer to the basestation, as determined, for example, by a signal strength or signalquality of communications with the base station.

In some examples, the uplink channel for which the configuration isselected may include a PUSCH, a PUCCH, or a PRACH. In some examples, theuplink channel may include a UL-MIMO channel. When the channel includesa PRACH, the PRACH may be transmitted on one or more pre-allocatedinterlaces.

In some examples, the waveform generator module 1245 may be used togenerate a waveform based on the selected configuration. When theselected configuration is an OFDMA configuration, the generated waveformmay be an OFDMA waveform. When the selected configuration is an SC-FDMAconfiguration, the generated waveform may be an SC-FDMA waveform. Whenthe selected configuration is an RB interleaved FDMA configuration, thegenerated waveform may be an RB interleaved FDMA waveform.

In some examples, the waveform communication module 1250 may be used tocommunicate (e.g., transmit) the generated waveform in a signal in theunlicensed radio frequency spectrum band using the uplink channel. Thesignal may be transmitted via the unlicensed radio frequency spectrumband transmitter module 1234.

In some examples, the wireless communication management module 1220 maybe used to communicate the configuration it selects to a base station.In other cases, the base station may blindly detect which configurationthe apparatus 1215 selected (e.g., based on a waveform received from theapparatus 1215 over the unlicensed radio frequency spectrum band).

FIG. 13 shows a block diagram 1300 of an apparatus 1315 for use inwireless communication (e.g., to identify an OFDMA configuration of anuplink channel for uplink communications in an unlicensed radiofrequency spectrum band), in accordance with various aspects of thepresent disclosure. In some examples, the apparatus 1315 may be anexample of aspects of one or more of the UEs 115, 215, and/or 1815described with reference to FIGS. 1, 2A, 2B, and/or 18, and/or aspectsof one or more of the apparatuses 1115, 1215, 1415, 1515, and/or 1615described with reference to FIGS. 11, 12, 14, 15, and/or 16. Theapparatus 1315 may also be a processor. The apparatus 1315 may include areceiver module 1310, a wireless communication management module 1320,and/or a transmitter module 1330. Each of these components may be incommunication with each other.

The components of the apparatus 1315 may, individually or collectively,be implemented using one or more ASICs adapted to perform some or all ofthe applicable functions in hardware. Alternatively, the functions maybe performed by one or more other processing units (or cores), on one ormore integrated circuits. In other examples, other types of integratedcircuits may be used (e.g., Structured/Platform ASICs, FPGAs, and otherSemi-Custom ICs), which may be programmed in any manner known in theart. The functions of each unit may also be implemented, in whole or inpart, with instructions embodied in a memory, formatted to be executedby one or more general or application-specific processors.

In some examples, the receiver module 1310 may be or include a radiofrequency (RF) receiver, such as an RF receiver operable to receivetransmissions in a first radio frequency spectrum band (e.g., a licensedradio frequency spectrum band usable for LTE/LTE-A communications)and/or a second radio frequency spectrum band (e.g., an unlicensed radiofrequency spectrum band, such as a shared radio frequency spectrum bandusable for Wi-Fi and/or LTE/LTE-A communications). The RF receiver mayinclude separate receivers for the first radio frequency spectrum bandand the second radio frequency spectrum band. The separate receiversmay, in some examples, take the form of a licensed radio frequencyspectrum band receiver module 1312 for communicating over the firstradio frequency spectrum band, and an unlicensed radio frequencyspectrum band receiver module 1314 for communicating over the secondradio frequency spectrum band. The receiver module 1310, including thelicensed radio frequency spectrum band receiver module 1312 and/or theunlicensed radio frequency spectrum band receiver module 1314, may beused to receive various types of data and/or control signals (i.e.,transmissions) over one or more communication links of a wirelesscommunication system including the first and second radio frequencyspectrum bands, such as one or more communication links of the wirelesscommunication system 100, 200, and/or 250 described with reference toFIGS. 1, 2A, and/or 2B.

In some examples, the transmitter module 1330 may be or include an RFtransmitter, such as an RF transmitter operable to transmit in the firstradio frequency spectrum band and/or the second radio frequency spectrumband. The RF transmitter may include separate transmitters for the firstradio frequency spectrum band and the second radio frequency spectrumband. The separate transmitters may, in some examples, take the form ofa licensed radio frequency spectrum band transmitter module 1332 forcommunicating over the first radio frequency spectrum band, and anunlicensed radio frequency spectrum band transmitter module 1334 forcommunicating over the second radio frequency spectrum band. Thetransmitter module 1330, including the licensed radio frequency spectrumband transmitter module 1332 and/or the unlicensed radio frequencyspectrum band transmitter module 1334, may be used to transmit varioustypes of data and/or control signals (i.e., transmissions) over one ormore communication links of the wireless communication system includingthe first radio frequency spectrum band and the second radio frequencyspectrum band.

In some examples, the wireless communication management module 1320 maybe an example of one or more aspects of the wireless communicationmanagement module 1120 described with reference to FIG. 11 and mayinclude an uplink channel configuration identifier module 1340, awaveform generator module 1345, and/or a waveform communication module1350. Each of these components may be in communication with each other.

In some examples, the uplink channel configuration identifier module1340 may be used to identify an OFDMA configuration of an uplink channelfor uplink communications (e.g., LTE/LTE-A uplink communications) in anunlicensed radio frequency spectrum band.

In some examples, the uplink channel for which the configuration isidentified may include a PUSCH, a PUCCH, or a PRACH. In some examples,the uplink channel may include a UL-MIMO channel. When the channelincludes a PRACH, the PRACH may be transmitted on one or morepre-allocated interlaces.

In some examples, the waveform generator module 1345 may be used togenerate an OFDMA waveform based on the identified OFDMA configuration.

In some examples, the waveform communication module 1350 may be used tocommunicate (e.g., transmit) the generated OFDMA waveform in a signal inthe unlicensed radio frequency spectrum band using the uplink channel.The signal may be transmitted via the unlicensed radio frequencyspectrum band transmitter module 1334.

FIG. 14 shows a block diagram 1400 of an apparatus 1415 for use inwireless communication (e.g., to identify an OFDMA configuration of anuplink channel for uplink communications in an unlicensed radiofrequency spectrum band), in accordance with various aspects of thepresent disclosure. In some examples, the apparatus 1415 may be anexample of aspects of one or more of the UEs 115, 215, and/or 1815described with reference to FIGS. 1, 2A, 2B, and/or 18, and/or aspectsof one or more of the apparatuses 1115, 1215, 1315, 1515, and/or 1615described with reference to FIGS. 11, 12, 13, 15, and/or 16. Theapparatus 1415 may also be a processor. The apparatus 1415 may include areceiver module 1410, a wireless communication management module 1420,and/or a transmitter module 1430. Each of these components may be incommunication with each other.

The components of the apparatus 1415 may, individually or collectively,be implemented using one or more ASICs adapted to perform some or all ofthe applicable functions in hardware. Alternatively, the functions maybe performed by one or more other processing units (or cores), on one ormore integrated circuits. In other examples, other types of integratedcircuits may be used (e.g., Structured/Platform ASICs, FPGAs, and otherSemi-Custom ICs), which may be programmed in any manner known in theart. The functions of each unit may also be implemented, in whole or inpart, with instructions embodied in a memory, formatted to be executedby one or more general or application-specific processors.

In some examples, the receiver module 1410 may be or include a radiofrequency (RF) receiver, such as an RF receiver operable to receivetransmissions in a first radio frequency spectrum band (e.g., a licensedradio frequency spectrum band usable for LTE/LTE-A communications)and/or a second radio frequency spectrum band (e.g., an unlicensed radiofrequency spectrum band, such as a shared radio frequency spectrum bandusable for WiFi and/or LTE/LTE-A communications). The RF receiver mayinclude separate receivers for the first radio frequency spectrum bandand the second radio frequency spectrum band. The separate receiversmay, in some examples, take the form of a licensed radio frequencyspectrum band receiver module 1412 for communicating over the firstradio frequency spectrum band, and an unlicensed radio frequencyspectrum band receiver module 1414 for communicating over the secondradio frequency spectrum band. The receiver module 1410, including thelicensed radio frequency spectrum band receiver module 1412 and/or theunlicensed radio frequency spectrum band receiver module 1414, may beused to receive various types of data and/or control signals (i.e.,transmissions) over one or more communication links of a wirelesscommunication system including the first and second radio frequencyspectrum bands, such as one or more communication links of the wirelesscommunication system 100, 200, and/or 250 described with reference toFIGS. 1, 2A, and/or 2B.

In some examples, the transmitter module 1430 may be or include an RFtransmitter, such as an RF transmitter operable to transmit in the firstradio frequency spectrum band and/or the second radio frequency spectrumband. The RF transmitter may include separate transmitters for the firstradio frequency spectrum band and the second radio frequency spectrumband. The separate transmitters may, in some examples, take the form ofa licensed radio frequency spectrum band transmitter module 1432 forcommunicating over the first radio frequency spectrum band, and anunlicensed radio frequency spectrum band transmitter module 1434 forcommunicating over the second radio frequency spectrum band. Thetransmitter module 1430, including the licensed radio frequency spectrumband transmitter module 1432 and/or the unlicensed radio frequencyspectrum band transmitter module 1434, may be used to transmit varioustypes of data and/or control signals (i.e., transmissions) over one ormore communication links of the wireless communication system includingthe first radio frequency spectrum band and the second radio frequencyspectrum band.

In some examples, the wireless communication management module 1420 maybe an example of one or more aspects of the wireless communicationmanagement module 1120 and/or 1320 described with reference to FIGS. 11and/or 13 and may include an uplink channel configuration identifiermodule 1440, a waveform generator module 1445, a waveform communicationmodule 1450, a data channel module 1460, a control channel module 1480,an SRS module 1485, a CSI-RS module 1490, and/or a control and datamultiplexing module 1495. Each of these components may be incommunication with each other.

In some examples, the uplink channel configuration identifier module1440 may be used to identify an OFDMA configuration of an uplink channelfor uplink communications (e.g., LTE/LTE-A uplink communications) in anunlicensed radio frequency spectrum band.

In some examples, the uplink channel for which the configuration isidentified may include a PUSCH, a PUCCH, or a PRACH. In some examples,the uplink channel may include a UL-MIMO channel. When the channelincludes a PRACH, the PRACH may be transmitted on one or morepre-allocated interlaces.

In some examples, the waveform generator module 1445 may be used togenerate an OFDMA waveform based on the identified OFDMA configuration.

In some examples, the waveform communication module 1450 may be used tocommunicate (e.g., transmit) the generated OFDMA waveform in a signal inthe unlicensed radio frequency spectrum band using the uplink channel.The signal may be transmitted via the unlicensed radio frequencyspectrum band transmitter module 1434.

In some examples, the data channel module 1460 may include a resourceallocation module 1462, a physical resource block (PRB) bundling module1464, a precoder cycling module 1466, a symbol mapping module 1468, asymbol power reduction module 1470, a DM-RS module 1472. The datachannel module 1460 may be used, for example, to manage theconfiguration, generation, and/or transmission of a PUSCH.

In some examples, the resource allocation module 1462 may be used toallocate resources for the uplink channel. In some examples, theallocation of resources may be based at least in part on a bitmap, andmay include, for example, Type 0 and Type 1 resource blocks. Also oralternately, the allocation of resources may be based at least in parton a starting resource block and a number of resource blocks (e.g., theallocation of resources may be resource indication value (RIV) basedwith Type 2 localized or Modified Type 2 distributed resource blocks).

In some examples, the PRB bundling module 1464 may be used to apply PRBbundling when generating the OFDMA waveform. The PRB bundling may begrant specific (e.g., all physical resource blocks in a transmission fora PUSCH may be bundled).

In some examples, the precoder cycling module 1466 may be used to applyprecoder cycling when generating the OFDMA waveform. In some examples,the precoder cycling may include cycling through a pre-defined set ofprecoders.

In some examples, the symbol mapping module 1468 may be used to map oneor more modulation symbols. In some examples, the symbol mapping module1468 may map modulation symbols to one or more resource elementsaccording to one or more OFDMA symbol positions. In the same or othercases, the symbol mapping module 1468 may map modulation symbols to oneor more resource elements according to one or more frequencysub-carriers. The symbol mapping module 1468 may also or alternately mapmodulation symbols to one or more resource elements according to aninterleaving of time slots and frequency sub-carriers.

In some examples, the symbol power reduction module 1470 may be used toreduce symbol power. For example, the symbol power reduction module 1470may apply symbol permutation or phase rotation, to reduce a metricindicating symbol power, when generating the OFDMA waveform. The symbolpower reduction module 1470 may also, or alternately, apply differentscrambling sequences to the OFDMA waveform, and may select one of thescrambling sequences for use when communicating the generated OFDMAwaveform in the signal in the unlicensed radio frequency spectrum band.

In some examples, the DM-RS module 1472 may be used to transmit a DM-RSon the uplink channel. The DM-RS module 1472 may transmit the DM-RS in aset of one or more time slots and one or more frequency sub-carriers.The DM-RS module 1472 may transmit the DM-RS in conjunction withcommunicating the generated OFDMA waveform.

In some examples, the set of one or more time slots and one or morefrequency sub-carriers in which the DM-RS is transmitted may be the sameas a set of one or more time slots and one or more frequencysub-carriers used to receive a UE-RS on a downlink channel (e.g., asdescribed with reference to FIG. 5 and FIG. 6). In other cases, the setof one or more time slots and one or more frequency sub-carriers inwhich the DM-RS is transmitted may differ in at least one respect from aset of one or more time slots and one or more frequency sub-carriersused to receive a UE-RS on a downlink channel (e.g., as described withreference to FIG. 5 and FIG. 7). The downlink channel may be a downlinkchannel used for downlink communications (e.g., LTE/LTE-A downlinkcommunications) in the licensed radio frequency spectrum band or theunlicensed radio frequency spectrum band.

In some examples, the control channel module 1480 may be used to managethe configuration, generation, and/or transmission of a PUSCH. In someexamples, the control channel module 1480 may be used to manage thetransmission of duplicate copies of the PUCCH in a plurality ofinterleaved resource blocks, as described, for example, with referenceto FIG. 8A. In other cases, the control channel module 1480 may be usedto manage transmission of the PUCCH within a plurality of interleavedresource blocks, according to a code division multiplexing sequence orother orthogonal sequence, as described, for example, with reference toFIG. 8A. In other cases, the control channel module 1480 may be used tomultiplex the PUCCH within a plurality of resource elements of anenhanced resource element group, as described, for example, withreference to FIG. 8B.

In some examples, the SRS module 1485 may be used to manage theconfiguration, generation, and/or transmission of an SRS on the uplinkchannel. The SRS may be located in an OFDM symbol of a subframe that isdifferent from a last OFDM symbol of the subframe, as described, forexample, with reference to FIG. 4. In other cases, the SRS may belocated in the last OFDM symbol of the subframe.

The SRS may, in some examples, be configured similarly to how SRS isconfigured for an LTE/LTE-A uplink channel in a licensed radio frequencyspectrum band (e.g., the SRS may be Zadoff-Chu (ZC) sequence based).

In some examples, the CSI-RS module 1490 may be used to manage theconfiguration, generation, and/or transmission of a CSI-RS on the uplinkchannel. In some examples, the CSI-RS may be transmitted independent ofan allocation of resources and on all resource blocks. In some examples,the CSI-RS may be transmitted depending on a resource allocation. TheCSI-RS may be wideband and include N tones per resource block. Thesymbols used for CSI-RS may be pre-defined or defined through controlchannel (e.g., PUCCH) or radio resource control (RRC) signaling. TheCSI-RS module 1490 may be used to indicate a rate matching required forPUSCH and PUCCH, to accommodate transmission of the CSI-RS, to other UEsor apparatuses that are frequency multiplexed on a same uplink subframeof the uplink channel as the apparatus 1415. The CSI-RS module 1490 mayalso be used to manage the configuration, generation, and/ortransmission of a channel state information interference measurement(CSI-IM) on the uplink channel.

In some examples, the control and data multiplexing module 1495 may beused to manage the transmission of the uplink channel based on whetherthe uplink channel includes a control channel (e.g., a PUCCH) and/or adata channel (e.g., a PUSCH). For example, when the uplink channelincludes the PUCCH but not the PUSCH, the control and data multiplexingmodule 1495 may configure the waveform communication module 1450 totransmit the uplink channel using a first set of resource blocks. Whenthe uplink channel includes the PUSCH but not the PUCCH, the control anddata multiplexing module 1495 may configure the waveform communicationmodule 1450 to transmit the uplink channel using a second set ofresource blocks, which second set of resource blocks is different fromthe first set of resource blocks. When the uplink channel includes boththe PUSCH and the PUCCH, the control and data multiplexing module 1495may configure the waveform communication module 1450 to frequencydivision multiplex the PUCCH and the PUSCH. In some examples, thewaveform communication module 1450 may be configured to frequencydivision multiplex the PUCCH and the PUSCH by transmitting the PUCCH ona subset of less than all of the first set of resource blocks, and bytransmitting the PUSCH on at least some of the second set of resourceblocks, as described, for example, with reference to FIG. 10. In othercases, the waveform communication module 1450 may be configured tofrequency division multiplex the PUCCH and the PUSCH by puncturing atleast one frequency sub-carrier of at least one RB of the first set ofresource blocks to transmit at least part of the PUSCH.

FIG. 15 shows a block diagram 1500 of an apparatus 1515 for use inwireless communication (e.g., to identify a set of common resourceblocks for transmission of a DM-RS in an uplink channel for uplinkcommunications in an unlicensed radio frequency spectrum band), inaccordance with various aspects of the present disclosure. In someexamples, the apparatus 1515 may be an example of aspects of one or moreof the UEs 115, 215, and/or 1815 described with reference to FIGS. 1,2A, 2B, and/or 18, aspects of one or more of the base stations 105, 205,and/or 1705 described with reference to FIGS. 1, 2A, 2B, and/or 17,and/or aspects of one or more of the apparatuses 1115, 1215, 1315, 1415,and/or 1615 described with reference to FIGS. 11, 12, 13, 14, and/or 16.The apparatus 1515 may also be a processor. The apparatus 1515 mayinclude a receiver module 1510, a wireless communication managementmodule 1520, and/or a transmitter module 1530. Each of these componentsmay be in communication with each other.

The components of the apparatus 1515 may, individually or collectively,be implemented using one or more ASICs adapted to perform some or all ofthe applicable functions in hardware. Alternatively, the functions maybe performed by one or more other processing units (or cores), on one ormore integrated circuits. In other examples, other types of integratedcircuits may be used (e.g., Structured/Platform ASICs, FPGAs, and otherSemi-Custom ICs), which may be programmed in any manner known in theart. The functions of each unit may also be implemented, in whole or inpart, with instructions embodied in a memory, formatted to be executedby one or more general or application-specific processors.

In some examples, the receiver module 1510 may be or include a radiofrequency (RF) receiver, such as an RF receiver operable to receivetransmissions in a first radio frequency spectrum band (e.g., a licensedradio frequency spectrum band usable for LTE/LTE-A communications)and/or a second radio frequency spectrum band (e.g., an unlicensed radiofrequency spectrum band, such as a shared radio frequency spectrum bandusable for Wi-Fi and/or LTE/LTE-A communications). The RF receiver mayinclude separate receivers for the first radio frequency spectrum bandand the second radio frequency spectrum band. The separate receiversmay, in some examples, take the form of a licensed radio frequencyspectrum band receiver module 1512 for communicating over the firstradio frequency spectrum band, and an unlicensed radio frequencyspectrum band receiver module 1514 for communicating over the secondradio frequency spectrum band. The receiver module 1510, including thelicensed radio frequency spectrum band receiver module 1512 and/or theunlicensed radio frequency spectrum band receiver module 1514, may beused to receive various types of data and/or control signals (i.e.,transmissions) over one or more communication links of a wirelesscommunication system including the first and second radio frequencyspectrum bands, such as one or more communication links of the wirelesscommunication system 100, 200, and/or 250 described with reference toFIGS. 1, 2A, and/or 2B.

In some examples, the transmitter module 1530 may be or include an RFtransmitter, such as an RF transmitter operable to transmit in the firstradio frequency spectrum band and/or the second radio frequency spectrumband. The RF transmitter may include separate transmitters for the firstradio frequency spectrum band and the second radio frequency spectrumband. The separate transmitters may, in some examples, take the form ofa licensed radio frequency spectrum band transmitter module 1532 forcommunicating over the first radio frequency spectrum band, and anunlicensed radio frequency spectrum band transmitter module 1534 forcommunicating over the second radio frequency spectrum band. Thetransmitter module 1530, including the licensed radio frequency spectrumband transmitter module 1532 and/or the unlicensed radio frequencyspectrum band transmitter module 1534, may be used to transmit varioustypes of data and/or control signals (i.e., transmissions) over one ormore communication links of the wireless communication system includingthe first radio frequency spectrum band and the second radio frequencyspectrum band.

In some examples, the wireless communication management module 1520 maybe an example of one or more aspects of the wireless communicationmanagement module 1120 described with reference to FIG. 11 and mayinclude a virtual cell identifier association module 1540 and/or acommon RB identifier module 1545. Each of these components may be incommunication with each other.

In some examples, the virtual cell identifier association module 1540may be used to associate a virtual cell identifier of a first basestation with transmissions between the first base station and theapparatus 1515. The virtual cell identifier may also be associated withtransmissions between a second base station and a second apparatus. Thetransmissions between the first base station and the apparatus 1515, andbetween the second base station and the second apparatus, may, in someexamples, be communications (e.g., LTE/LTE-A communications) in anunlicensed radio frequency spectrum band (e.g., a shared radio frequencyspectrum band usable for Wi-Fi and/or LTE/LTE-A communications).

In some examples, the common RB identifier module 1545 may be used toidentify a set of common resource blocks for transmission of a DM-RS inan uplink channel and a downlink channel between the first base stationand the apparatus 1515. The identification of the set of common resourceblocks may be based at least in part on the virtual cell identifierassociated with transmissions between the first base station and theapparatus 1515.

FIG. 16 shows a block diagram 1600 of an apparatus 1615 for use inwireless communication (e.g., to identify a set of common resourceblocks for transmission of a DM-RS in an uplink channel for uplinkcommunications in an unlicensed radio frequency spectrum band), inaccordance with various aspects of the present disclosure. In someexamples, the apparatus 1615 may be an example of aspects of one or moreof the UEs 115, 215, and/or 1815 described with reference to FIGS. 1,2A, 2B, and/or 18, aspects of one or more of the base stations 105, 205,and/or 1705 described with reference to FIGS. 1, 2A, 2B, and/or 17,and/or aspects of one or more of the apparatuses 1115, 1215, 1315, 1415,and/or 1515 described with reference to FIGS. 11, 12, 13, 14, and/or 15.The apparatus 1615 may also be a processor. The apparatus 1615 mayinclude a receiver module 1610, a wireless communication managementmodule 1620, and/or a transmitter module 1630. Each of these componentsmay be in communication with each other.

The components of the apparatus 1615 may, individually or collectively,be implemented using one or more ASICs adapted to perform some or all ofthe applicable functions in hardware. Alternatively, the functions maybe performed by one or more other processing units (or cores), on one ormore integrated circuits. In other examples, other types of integratedcircuits may be used (e.g., Structured/Platform ASICs, FPGAs, and otherSemi-Custom ICs), which may be programmed in any manner known in theart. The functions of each unit may also be implemented, in whole or inpart, with instructions embodied in a memory, formatted to be executedby one or more general or application-specific processors.

In some examples, the receiver module 1610 may be or include a radiofrequency (RF) receiver, such as an RF receiver operable to receivetransmissions in a first radio frequency spectrum band (e.g., a licensedradio frequency spectrum band usable for LTE/LTE-A communications)and/or a second radio frequency spectrum band (e.g., an unlicensed radiofrequency spectrum band, such as a shared radio frequency spectrum bandusable for Wi-Fi and/or LTE/LTE-A communications). The RF receiver mayinclude separate receivers for the first radio frequency spectrum bandand the second radio frequency spectrum band. The separate receiversmay, in some examples, take the form of a licensed radio frequencyspectrum band receiver module 1612 for communicating over the firstradio frequency spectrum band, and an unlicensed radio frequencyspectrum band receiver module 1614 for communicating over the secondradio frequency spectrum band. The receiver module 1610, including thelicensed radio frequency spectrum band receiver module 1612 and/or theunlicensed radio frequency spectrum band receiver module 1614, may beused to receive various types of data and/or control signals (i.e.,transmissions) over one or more communication links of a wirelesscommunication system including the first and second radio frequencyspectrum bands, such as one or more communication links of the wirelesscommunication system 100, 200, and/or 250 described with reference toFIGS. 1, 2A, and/or 2B.

In some examples, the transmitter module 1630 may be or include an RFtransmitter, such as an RF transmitter operable to transmit in the firstradio frequency spectrum band and/or the second radio frequency spectrumband. The RF transmitter may include separate transmitters for the firstradio frequency spectrum band and the second radio frequency spectrumband. The separate transmitters may, in some examples, take the form ofa licensed radio frequency spectrum band transmitter module 1632 forcommunicating over the first radio frequency spectrum band, and anunlicensed radio frequency spectrum band transmitter module 1634 forcommunicating over the second radio frequency spectrum band. Thetransmitter module 1630, including the licensed radio frequency spectrumband transmitter module 1632 and/or the unlicensed radio frequencyspectrum band transmitter module 1634, may be used to transmit varioustypes of data and/or control signals (i.e., transmissions) over one ormore communication links of the wireless communication system includingthe first radio frequency spectrum band and the second radio frequencyspectrum band.

In some examples, the wireless communication management module 1620 maybe an example of one or more aspects of the wireless communicationmanagement module 1120 described with reference to FIG. 11 and mayinclude a virtual cell identifier association module 1640, a common RBidentifier module 1645, a link identifier association module 1650, aDM-RS port identification module 1655, and/or a waveform communicationmodule 1660. Each of these components may be in communication with eachother.

In some examples, the virtual cell identifier association module 1640may be used to associate a virtual cell identifier of a first basestation with transmissions between the first base station and theapparatus 1615. The virtual cell identifier may also be associated withtransmissions between a second base station and a second apparatus. Thetransmissions between the first base station and the apparatus 1615, andbetween the second base station and the second apparatus, may, in someexamples, be communications (e.g., LTE/LTE-A communications) in anunlicensed radio frequency spectrum band (e.g., a shared radio frequencyspectrum band usable for Wi-Fi and/or LTE/LTE-A communications).

In some examples, the common RB identifier module 1645 may be used toidentify a set of common resource blocks for transmission of a DM-RS inan uplink channel and a downlink channel between the first base stationand the apparatus 1615. The identification of the set of common resourceblocks may be based at least in part on the virtual cell identifierassociated with transmissions between the first base station and theapparatus 1615.

In some examples, the link identifier association module 1650 may beused to associate a first link identifier with the uplink channelbetween the first base station and the apparatus 1615, and to associatea second link identifier with the downlink channel between the firstbase station and the apparatus 1615, where the first link identifier isdifferent from the second link identifier.

In some examples, the DM-RS port identification module 1655 may be usedto identify a port associated with a first spatial multiplexing fortransmission of the DM-RS between the first base station and theapparatus 1615. The first spatial multiplexing may be different from asecond spatial multiplexing associated with a port used to transmit aDM-RS between the second base station and the second apparatus.

In some examples, the waveform communication module 1660 may be used totransmit the first link identifier with transmissions in the uplinkchannel or transmit the second link identifier with transmissions in thedownlink channel. The transmissions may be made via the identified port.In some examples, transmitting the first link identifier withtransmissions in the uplink channel may include generating the DM-RS asa function of the first link identifier. In other cases, transmittingthe second link identifier with transmissions in the downlink channelmay include generating the DM-RS as a function of the second linkidentifier.

FIG. 17 shows a block diagram 1700 of a base station 1705 for use inwireless communication, in accordance with various aspects of thepresent disclosure. In some examples, the base station 1705 may be anexample of one or more aspects of one of the base stations 105 and/or205 described with reference to FIGS. 1, 2A, and/or 2B, and/or one ofthe apparatuses 1115, 1515, and/or 1615 described with reference toFIGS. 11, 15, and/or 16. The base station 1705 may be configured toimplement or facilitate at least some of the features and functionsdescribed with reference to FIGS. 1, 2A, 2B, 5, 6, 7, 8A, 8B, 9, 10, 11,15, and/or 16. The base station 1705 may include a processor module1710, a memory module 1720, at least one transceiver module (representedby transceiver module(s) 1755), at least one antenna (represented byantenna(s) 1760), and/or a base station RF spectrum band module 1770.The base station 1705 may also include one or more of a base stationcommunications module 1730, a network communications module 1740, and asystem communications management module 1750. Each of these componentsmay be in communication with each other, directly or indirectly, overone or more buses 1735.

The memory module 1720 may include RAM and/or ROM. The memory module1720 may store computer-readable, computer-executable software (SW) code1725 containing instructions that are configured to, when executed,cause the processor module 1710 to perform various functions describedherein for communicating (or managing communications) over a first radiofrequency spectrum band (e.g., a licensed radio frequency spectrum bandusable for LTE/LTE-A communications) and/or a second radio frequencyspectrum band (e.g., an unlicensed radio frequency spectrum band usablefor LTE/LTE-A communications). Alternatively, the software code 1725 maynot be directly executable by the processor module 1710 but beconfigured to cause the base station 1705 (e.g., when compiled andexecuted) to perform various of the functions described herein.

The processor module 1710 may include an intelligent hardware device,e.g., a central processing unit (CPU), a microcontroller, an ASIC, etc.The processor module 1710 may process information received through thetransceiver module(s) 1755, the base station communications module 1730,and/or the network communications module 1740. The processor module 1710may also process information to be sent to the transceiver module(s)1755 for transmission through the antenna(s) 1760, to the base stationcommunications module 1730 for transmission to one or more other basestations 1705-a and 1705-b, and/or to the network communications module1740 for transmission to a core network 1745, which may be an example ofaspects of the core network 130 described with reference to FIG. 1. Theprocessor module 1710 may handle, alone or in connection with the basestation RF spectrum band module 1770, various aspects of communicatingover (or managing communications over) the first radio frequencyspectrum band and/or the second radio frequency spectrum band.

The transceiver module(s) 1755 may include a modem configured tomodulate packets and provide the modulated packets to the antenna(s)1760 for transmission, and to demodulate packets received from theantenna(s) 1760. The transceiver module(s) 1755 may, in some examples,be implemented as one or more transmitter modules and one or moreseparate receiver modules. The transceiver module(s) 1755 may supportcommunications in the first radio frequency spectrum band and/or thesecond radio frequency spectrum band. The transceiver module(s) 1755 maybe configured to communicate bi-directionally, via the antenna(s) 1760,with one or more of the UEs 115, 215, 1215, 1315, and/or 1415 describedwith reference to FIGS. 1, 2A, 2B, 12A, 13, and/or 14, for example. Thebase station 1705 may typically include multiple antennas 1760 (e.g., anantenna array). The base station 1705 may communicate with the corenetwork 1745 through the network communications module 1740. The basestation 1705 may also communicate with other base stations or eNBs, suchas the eNBs 1705-a and 1705-b, using the base station communicationsmodule 1730.

According to the architecture of FIG. 17, the system communicationsmanagement module 1750 may manage communications with other basestations and/or apparatuses. In some examples, functionality of thesystem communications management module 1750 may be implemented as acomponent of the transceiver module(s) 1755, as a computer programproduct, and/or as one or more controller elements of the processormodule 1710.

The base station RF spectrum band module 1770 may be configured toperform, control, and/or facilitate some or all of the features and/orfunctions described with reference to FIGS. 1, 2A, 2B, 5, 6, 7, 8A, 8B,9, 10, 11, 15, and/or 16 related to wireless communication in the firstradio frequency spectrum band and/or the second radio frequency spectrumband. In some examples, the base station RF spectrum band module 1770may be configured to support a supplemental downlink mode, a carrieraggregation mode, and/or a standalone mode of operation in the secondradio frequency spectrum band. The base station RF spectrum band module1770 may include an LTE/LTE-A module 1775 configured to handle LTE/LTE-Acommunications in a licensed radio frequency spectrum band, an LTE/LTE-Aunlicensed module 1780 configured to handle LTE/LTE-A communications inan unlicensed radio frequency spectrum band, and/or an unlicensed module1785 configured to handle communications other than LTE/LTE-Acommunications in an unlicensed radio frequency spectrum band. The basestation RF spectrum band module 1770 may also include communicationmanagement module 1790. The communication management module 1790 maymanage some or all of the communications with UEs and/or apparatusessuch as the UEs 115, 215, and/or 1815 described with reference to FIGS.1, 2A, 2B, and/or 18, and/or the apparatuses 1115, 1215, 1315, 1415,1515, and/or 1615 described with reference to FIGS. 11, 12, 13, 14, 15,and/or 16. In some examples, and by way of example, the communicationmanagement module 1790 may be an example of one or more aspects of thewireless communication management module 1120, 1520, and/or 1620described with reference to FIGS. 11, 15, and/or 16. The base station RFspectrum band module 1770, or portions of it, may include a processor,and/or some or all of the functions of the base station RF spectrum bandmodule 1770 may be performed by the processor module 1710 and/or inconnection with the processor module 1710.

FIG. 18 shows a block diagram 1800 of a UE 1815 for use in wirelesscommunication, in accordance with various aspects of the presentdisclosure. The UE 1815 may have various configurations and may beincluded or be part of a personal computer (e.g., a laptop computer,netbook computer, tablet computer, etc.), a cellular telephone, a PDA, adigital video recorder (DVR), an internet appliance, a gaming console,an e-reader, etc. The UE 1815 may, in some examples, have an internalpower supply (not shown), such as a small battery, to facilitate mobileoperation. In some examples, the UE 1815 may be an example of one ormore aspects of one of the UEs 115 and/or 215 described with referenceto FIGS. 1, 2A, and/or 2B, and/or one of the apparatuses 1115, 1215,1315, 1415, 1515, and/or 1615 described with reference to FIGS. 11, 12,13, 14, 15, and/or 16. The UE 1815 may be configured to implement atleast some of the features and functions described with reference toFIGS. 1, 2A, 2B, 5, 6, 7, 8A, 8B, 9, 10, 11, 12, 13, 14, 15, and/or 16.

The UE 1815 may include a processor module 1810, a memory module 1820,at least one transceiver module (represented by transceiver module(s)1870), at least one antenna (represented by antenna(s) 1880), and/or aUE RF spectrum band module 1840. Each of these components may be incommunication with each other, directly or indirectly, over one or morebuses 1835.

The memory module 1820 may include random access memory (RAM) and/orread-only memory (ROM). The memory module 1820 may storecomputer-readable, computer-executable software (SW) code 1825containing instructions that are configured to, when executed, cause theprocessor module 1810 to perform various functions described herein forcommunicating over (or managing communications over) a first radiofrequency spectrum band (e.g., a licensed radio frequency spectrum bandusable for LTE/LTE-A communications) and/or a second radio frequencyspectrum band (e.g., an unlicensed radio frequency spectrum band usablefor LTE/LTE-A communications). Alternatively, the software code 1825 maynot be directly executable by the processor module 1810 but beconfigured to cause the UE 1815 (e.g., when compiled and executed) toperform various of the functions described herein.

The processor module 1810 may include an intelligent hardware device,e.g., a CPU, a microcontroller, an ASIC, etc. The processor module 1810may process information received through the transceiver module(s) 1870and/or information to be sent to the transceiver module(s) 1870 fortransmission through the antenna(s) 1880. The processor module 1810 mayhandle, alone or in connection with the UE RF spectrum band module 1840,various aspects of communicating over (or managing communications over)the first radio frequency spectrum band and/or the second radiofrequency spectrum band.

The transceiver module(s) 1870 may include a modem configured tomodulate packets and provide the modulated packets to the antenna(s)1880 for transmission, and to demodulate packets received from theantenna(s) 1880. The transceiver module(s) 1870 may, in some examples,be implemented as one or more transmitter modules and one or moreseparate receiver modules. The transceiver module(s) 1870 may supportcommunications in the first radio frequency spectrum band and/or thesecond radio frequency spectrum band. The transceiver module(s) 1870 maybe configured to communicate bi-directionally, via the antenna(s) 1880,with one or more of the base stations 105, 205, and/or 1705 describedwith reference to FIGS. 1, 2A, 2B, and/or 17, and/or the apparatuses1115, 1515, and/or 1615 described with reference to FIGS. 11, 15, and/or16. While the UE 1815 may include a single antenna, there may beexamples in which the UE 1815 may include multiple antennas 1880.

The UE RF spectrum band module 1840 may be configured to perform and/orcontrol some or all of the features and/or functions described withreference to FIGS. 1, 2A, 2B, 5, 6, 7, 8A, 8B, 9, 10, 11, 12, 13, 14,15, and/or 16 related to wireless communication in the first radiofrequency spectrum band and/or the second radio frequency spectrum band.For example, the UE RF spectrum band module 1840 may be configured tosupport a supplemental downlink mode, a carrier aggregation mode, and/ora standalone mode of operation in the second radio frequency spectrumband. The UE RF spectrum band module 1840 may include an LTE/LTE-Amodule 1845 configured to handle LTE/LTE-A communications in a licensedradio frequency spectrum band, an LTE/LTE-A unlicensed module 1850configured to handle LTE/LTE-A communications in an unlicensed radiofrequency spectrum band, and/or an unlicensed module 1855 configured tohandle communications other than LTE/LTE-A communications in anunlicensed radio frequency spectrum band. The UE RF spectrum band module1840 may also include a communication management module 1860. In someexamples, and by way of example, the communication management module1860 may be an example of one or more aspects of the wirelesscommunication management module 1120, 1220, 1320, 1420, 1520, and/or1620 described with reference to FIGS. 11, 12, 13, 14, 15, and/or 16.The UE RF spectrum band module 1840, or portions of it, may include aprocessor, and/or some or all of the functions of the UE RF spectrumband module 1840 may be performed by the processor module 1810 and/or inconnection with the processor module 1810.

FIG. 19 is a flowchart illustrating an example of a method 1900 ofwireless communication, in accordance with various aspects of thepresent disclosure. For clarity, the method 1900 is described below withreference to aspects of one or more of the UEs 115, 215, and/or 1815described with reference to FIGS. 1, 2A, 2B, and/or 18, and/or aspectsof one or more of the apparatuses 1115 and/or 1215 described withreference to FIGS. 11 and/or 12. In some examples, a UE such as one ofthe UEs 115, 215, or 1815 or an apparatus such as one of the apparatuses1115 or 1215 may execute one or more sets of codes to control thefunctional elements of the UE or apparatus to perform the functionsdescribed below.

At block 1905, the method 1900 may include dynamically selecting aconfiguration of an uplink channel for uplink communications (e.g.,LTE/LTE-A uplink communications) in an unlicensed radio frequencyspectrum band (e.g., a shared radio frequency spectrum band usable forWi-Fi and/or LTE/LTE-A communications). In some examples, theconfiguration of the uplink channel may be selected from among an OFDMAconfiguration, an SC-FDMA configuration, and/or an RB interleaved FDMAconfiguration.

In some examples, the configuration of the uplink channel may beselected based at least in part on signaling received from a basestation (e.g., an eNB). In other cases, the configuration of the uplinkchannel may be selected based on its proximity to a base station. Forexample, a resource block level interleaved FDMA configuration or anOFDMA configuration may be selected when a UE or apparatus performingthe method 1900 is relatively closer to the base station, as determined,for example, by a signal strength or signal quality of communicationswith the base station.

The operation(s) at block 1905 may be performed using the wirelesscommunication management module 1120, 1220, and/or the communicationmanagement module 1860 described with reference to FIGS. 11, 12, and/or18, and/or the uplink channel configuration selector module 1240described with reference to FIG. 12.

At block 1910, the method 1900 may include generating a waveform basedon the selected configuration. When the selected configuration is anOFDMA configuration, the generated waveform may be an OFDMA waveform.When the selected configuration is an SC-FDMA configuration, thegenerated waveform may be an SC-FDMA waveform. When the selectedconfiguration is a resource block interleaved FDMA configuration, thegenerated waveform may be a resource block interleaved FDMA waveform.The operation(s) at block 1910 may be performed using the wirelesscommunication management module 1120, 1220, and/or the communicationmanagement module 1860 described with reference to FIGS. 11, 12, and/or18, and/or the waveform generator module 1245 described with referenceto FIG. 12.

At block 1915, the method 1900 may include communicating (e.g.,transmitting) the generated waveform in a signal in the unlicensed radiofrequency spectrum band using the uplink channel. The operation(s) atblock 1915 may be performed using the wireless communication managementmodule 1120, 1220, and/or the communication management module 1860described with reference to FIGS. 11, 12, and/or 18, the waveformcommunication module 1250 described with reference to FIG. 12, thetransmitter module 1130 and/or 1230 described with reference to FIGS. 11and/or 12, the unlicensed radio frequency spectrum band transmittermodule 1234 described with reference to FIG. 12, and/or the transceivermodule(s) 1870 described with reference to FIG. 18.

Thus, the method 1900 may provide for wireless communication. It shouldbe noted that the method 1900 is just one implementation and that theoperations of the method 1900 may be rearranged or otherwise modifiedsuch that other implementations are possible.

FIG. 20 is a flowchart illustrating an example of a method 2000 ofwireless communication, in accordance with various aspects of thepresent disclosure. For clarity, the method 2000 is described below withreference to aspects of one or more of the UEs 115, 215, and/or 1815described with reference to FIGS. 1, 2A, 2B, and/or 18, and/or aspectsof one or more of the apparatuses 1115 and/or 1215 described withreference to FIGS. 11 and/or 12. In some examples, a UE such as one ofthe UEs 115, 215, or 1815 or an apparatus such as one of the apparatuses1115 or 1215 may execute one or more sets of codes to control thefunctional elements of the UE or apparatus to perform the functionsdescribed below.

At block 2005, the method 2000 may include receiving signaling from abase station (e.g., an eNB). The signaling may, in some examples,indicate a resource block allocation. In some examples, the signalingmay be received over a downlink channel in a licensed radio frequencyspectrum band (e.g., an LTE/LTE-A radio frequency spectrum band usablefor LTE/LTE-A communications) or over a downlink channel in anunlicensed radio frequency spectrum band (e.g., a shared radio frequencyspectrum band usable for Wi-Fi and/or LTE/LTE-A communications). In someexamples, the signaling may include Layer 1 signaling (e.g., ePDCCH orPDCCH based signaling) and/or Layer 2 signaling (e.g., MAC header basedsignaling). The signaling may, in some examples, ask a UE or apparatusperforming the method 2000 to dynamically or semi-statically select aconfiguration of the uplink channel based at least in part on thereceived signaling.

The operation(s) at block 2005 may be performed using the receivermodule 1110 and/or 1210 described with reference to FIGS. 11 and/or 12,the transceiver module(s) 1870 described with reference to FIG. 18,and/or the wireless communication management module 1120, 1220, and/orthe communication management module 1860 described with reference toFIGS. 11, 12, and/or 18.

At block 2010, the method 2000 may include dynamically selecting aconfiguration of an uplink channel for uplink communications (e.g.,LTE/LTE-A uplink communications) in the unlicensed radio frequencyspectrum band. The selection may be based at least in part on thesignaling received at block 2005. In some examples, the configuration ofthe uplink channel may be selected from among an OFDMA configuration, anSC-FDMA configuration, and/or a resource block interleaved FDMAconfiguration. When the received signaling indicates a resource blockallocation, the configuration of the uplink channel may, in someexamples, be selected based on the resource block allocation.

In some examples, the uplink channel for which the configuration isselected may include a PUSCH, a PUCCH, or a PRACH. In some examples, theuplink channel may include a UL-MIMO channel. When the channel includesa PRACH, the PRACH may be transmitted on one or more pre-allocatedinterlaces, where an interlace is defined as a plurality ofnon-contiguous resource blocks. The non-contiguous resource blocks maybe selected in such a manner that the resource blocks span at least 80%of the available bandwidth of the unlicensed radio frequency spectrum.

At block 2015, the flow of the method 2000 may be altered based on theselected configuration. For example, when the selected configuration isan OFDMA configuration, the flow of the method 2000 may be directed toblock 2020. When the selected configuration is an SC-FDMA configuration,the flow of the method 2000 may be directed to block 2025. When theselected configuration is a resource block interleaved FDMAconfiguration, the flow of the method 2000 may be directed to block2030.

The operation(s) at block 2010 and/or block 2015 may be performed usingthe wireless communication management module 1120, 1220, and/or thecommunication management module 1860 described with reference to FIGS.11, 12, and/or 18, and/or the uplink channel configuration selectormodule 1240 described with reference to FIG. 12.

At block 2020, 2025, and/or 2030, the method 2000 may include generatinga waveform based on the selected configuration. When the selectedconfiguration is an OFDMA configuration, the waveform generated at block2020 may be an OFDMA waveform. When the selected configuration is anSC-FDMA configuration, the waveform generated at block 2025 may be anSC-FDMA waveform. When the selected configuration is a resource blockinterleaved FDMA configuration, the waveform generated at block 2030 maybe a resource block interleaved FDMA waveform. The operation(s) at block2020, 2025, and/or 2030 may be performed using the wirelesscommunication management module 1120, 1220, and/or the communicationmanagement module 1860 described with reference to FIGS. 11, 12, and/or18, and/or the waveform generator module 1245 described with referenceto FIG. 12.

At block 2035, the method 2000 may include communicating (e.g.,transmitting) the generated waveform in a signal in the unlicensed radiofrequency spectrum band using the uplink channel. The operation(s) atblock 2035 may be performed using the wireless communication managementmodule 1120, 1220, and/or the communication management module 1860described with reference to FIGS. 11, 12, and/or 18, the waveformcommunication module 1250 described with reference to FIG. 12, thetransmitter module 1130 and/or 1230 described with reference to FIGS. 11and/or 12, the unlicensed radio frequency spectrum band transmittermodule 1234 described with reference to FIG. 12, and/or the transceivermodule(s) 1870 described with reference to FIG. 18.

In some examples, a UE or apparatus performing the method 2000 maycommunicate the configuration it selects to a base station. In othercases, the base station may blindly detect which configuration the UE orapparatus selected (e.g., based on a waveform received from the UE orapparatus over the unlicensed radio frequency spectrum band).

Thus, the method 2000 may provide for wireless communication. It shouldbe noted that the method 2000 is just one implementation and that theoperations of the method 2000 may be rearranged or otherwise modifiedsuch that other implementations are possible. In an alternative to themethod 2000, a UE may or may not receive signaling from a base stationand may autonomously select a configuration of the uplink channel.

FIG. 21 is a flowchart illustrating an example of a method 2100 ofwireless communication, in accordance with various aspects of thepresent disclosure. For clarity, the method 2100 is described below withreference to aspects of one or more of the UEs 115, 215, and/or 1815described with reference to FIGS. 1, 2A, 2B, and/or 18, and/or aspectsof one or more of the apparatuses 1115, 1215, 1315, and/or 1415described with reference to FIGS. 11, 12, 13, and/or 14. In someexamples, a UE such as one of the UEs 115, 215, or 1815 or an apparatussuch as one of the apparatuses 1115, 1215, 1315, or 1415 may execute oneor more sets of codes to control the functional elements of the UE orapparatus to perform the functions described below.

At block 2105, the method 2100 may include identifying an OFDMAconfiguration of an uplink channel for uplink communications (e.g.,LTE/LTE-A uplink communications) in an unlicensed radio frequencyspectrum band (e.g., a shared radio frequency spectrum band usable forWi-Fi and/or LTE/LTE-A communications). The operation(s) at block 2105may be performed using the wireless communication management module1120, 1220, 1320, 1420, and/or the communication management module 1860described with reference to FIGS. 11, 12, 13, 14, and/or 18, the uplinkchannel configuration selector module 1240 described with reference toFIG. 12, and/or the uplink channel configuration identifier module 1340and/or 1440 described with reference to FIGS. 13 and/or 14.

In some examples, the uplink channel for which the configuration isidentified may include a PUSCH, a PUCCH, or a PRACH. In some examples,the uplink channel may include a UL-MIMO channel. When the channelincludes a PRACH, the PRACH may be transmitted on one or morepre-allocated interlaces.

At block 2110, the method 2100 may include generating an OFDMA waveformbased on the identified OFDMA configuration. The operation(s) at block2110 may be performed using the wireless communication management module1120, 1220, 1320, 1420, and/or the communication management module 1860described with reference to FIGS. 11, 12, 13, 14, and/or 18, and/or thewaveform generator module 1245, 1345, and/or 1445 described withreference to FIGS. 12, 13, and/or 14.

At block 2115, the method 2100 may include communicating (e.g.,transmitting) the generated OFDMA waveform in a signal in the unlicensedradio frequency spectrum band using the uplink channel. The operation(s)at block 2115 may be performed using the wireless communicationmanagement module 1120, 1220, 1320, 1420, and/or the communicationmanagement module 1860 described with reference to FIGS. 11, 12, 13, 14,and/or 18, the waveform communication module 1250, 1350, and/or 1450described with reference to FIGS. 12, 13, and/or 14, the transmittermodule 1130, 1230, 1330, and/or 1430 described with reference to FIGS.11, 12, 13, and/or 14, the unlicensed radio frequency spectrum bandtransmitter module 1234 and/or 1434 described with reference to FIGS. 12and/or 14, and/or the transceiver module(s) 1870 described withreference to FIG. 18.

Thus, the method 2100 may provide for wireless communication. It shouldbe noted that the method 2100 is just one implementation and that theoperations of the method 2100 may be rearranged or otherwise modifiedsuch that other implementations are possible.

FIG. 22 is a flowchart illustrating an example of a method 2200 ofwireless communication, in accordance with various aspects of thepresent disclosure. For clarity, the method 2200 is described below withreference to aspects of one or more of the UEs 115, 215, and/or 1815described with reference to FIGS. 1, 2A, 2B, and/or 18, and/or aspectsof one or more of the apparatuses 1115, 1215, 1315, and/or 1415described with reference to FIGS. 11, 12, 13, and/or 14. In someexamples, a UE such as one of the UEs 115, 215, or 1815 or an apparatussuch as one of the apparatuses 1115, 1215, 1315, or 1415 may execute oneor more sets of codes to control the functional elements of the UE orapparatus to perform the functions described below.

At block 2205, the method 2200 may include identifying an OFDMAconfiguration of an uplink channel for uplink communications (e.g.,LTE/LTE-A uplink communications) in an unlicensed radio frequencyspectrum band (e.g., a shared radio frequency spectrum band usable forWi-Fi and/or LTE/LTE-A communications). The uplink channel may include aPUSCH. In some examples, the uplink channel may include a UL-MIMOchannel. The operation(s) at block 2205 may be performed using thewireless communication management module 1120, 1220, 1320, 1420, and/orthe communication management module 1860 described with reference toFIGS. 11, 12, 13, 14, and/or 18, the uplink channel configurationselector module 1240 described with reference to FIG. 12, and/or theuplink channel configuration identifier module 1340 and/or 1440described with reference to FIGS. 13 and/or 14.

At block 2210, the method 2200 may include allocating resources for theuplink channel. In some examples, the allocation of resources may bebased at least in part on a bitmap, and may include, for example, Type 0and Type 1 resource blocks. Also or alternately, the allocation ofresources may be based at least in part on a starting resource block anda number of resource blocks (e.g., the allocation of resources may beresource indication value (RIV) based with Type 2 localized or ModifiedType 2 distributed resource blocks). The operation(s) at block 2210 maybe performed using the wireless communication management module 1120,1220, 1320, 1420, and/or the communication management module 1860described with reference to FIGS. 11, 12, 13, 14, and/or 18, and/or thedata channel module 1460 and/or the resource allocation module 1462described with reference to FIG. 14.

At block 2215, the method 2200 may include generating an OFDMA waveformbased on the identified configuration. The operation(s) at block 2215may be performed using the wireless communication management module1120, 1220, 1320, 1420, and/or 1860 described with reference to FIGS.11, 12, 13, 14, and/or 18, and/or the waveform generator module 1245,1345, and/or 1445 described with reference to FIGS. 12, 13, and/or 14.

In some examples, the method 2200 may include using PRB bundling and/orprecoder cycling when generating the OFDMA waveform. The PRB bundlingmay be grant specific (e.g., all physical resource blocks in atransmission for a PUSCH may be bundled). The precoder cycling mayinclude cycling through a pre-defined set of precoders. A precoder usedfor the precoder cycling may be indicated by a base station as part ofan uplink grant. The operation(s) at block 2220 may be performed usingthe wireless communication management module 1120, 1220, 1320, 1420,and/or the communication management module 1860 described with referenceto FIGS. 11, 12, 13, 14, and/or 18, and/or the data channel module 1460,the PRB bundling module 1464, and/or the precoder cycling module 1466described with reference to FIG. 14.

At block 2220, the method 2200 may include mapping one or moremodulation symbols. In some examples, the modulation symbols may bemapped to one or more resource elements according to one or more OFDMsymbol positions. In the same or other cases, the modulation symbols maybe mapped to one or more resource elements according to one or morefrequency sub-carriers. The modulation symbols may also or alternatelybe mapped to one or more resource elements according to an interleavingof time slots and frequency sub-carriers. The operation(s) at block 2220may be performed using the wireless communication management module1120, 1220, 1320, 1420, and/or the communication management module 1860described with reference to FIGS. 11, 12, 13, 14, and/or 18, and/or thedata channel module 1460 and/or the symbol mapping module 1468 describedwith reference to FIG. 14.

At block 2225, the method 2200 may include communicating (e.g.,transmitting) the generated OFDMA waveform in a signal in the unlicensedradio frequency spectrum band using the uplink channel. The operation(s)at block 2225 may be performed using the wireless communicationmanagement module 1120, 1220, 1320, 1420, and/or the communicationmanagement module 1860 described with reference to FIGS. 11, 12, 13, 14,and/or 18, the transmitter module 1130, 1230, 1330, and/or 1430described with reference to FIGS. 11, 12, 13, and/or 14, the waveformcommunication module 1250 described with reference to FIG. 12, theunlicensed radio frequency spectrum band transmitter module 1234 and/or1434 described with reference to FIGS. 12 and/or 14, and/or thetransceiver module(s) 1870 described with reference to FIG. 18.

In some examples, the method 2200 may include using one or moretechniques to reduce symbol power. For example, the method 2200 mayinclude applying symbol permutation or phase rotation to reduce a metricindicating symbol power when generating the OFDMA waveform. The method2200 may also, or alternately, include applying different scramblingsequences to the OFDMA waveform, and selecting one of the scramblingsequences for use when communicating the generated OFDMA waveform in thesignal in the unlicensed radio frequency spectrum band.

The technique(s) to reduce symbol power may be performed using thewireless communication management module 1120, 1220, 1320, 1420, and/orthe communication management module 1860 described with reference toFIGS. 11, 12, 13, 14, and/or 18, and/or the data channel module 1460and/or the symbol power reduction module 1470 described with referenceto FIG. 14.

Thus, the method 2200 may provide for wireless communication. It shouldbe noted that the method 2200 is just one implementation and that theoperations of the method 2200 may be rearranged or otherwise modifiedsuch that other implementations are possible.

FIG. 23 is a flowchart illustrating an example of a method 2300 ofwireless communication, in accordance with various aspects of thepresent disclosure. For clarity, the method 2300 is described below withreference to aspects of one or more of the UEs 115, 215, and/or 1815described with reference to FIGS. 1, 2A, 2B, and/or 18, and/or aspectsof one or more of the apparatuses 1115, 1215, 1315, and/or 1415described with reference to FIGS. 11, 12, 13, and/or 14. In someexamples, a UE such as one of the UEs 115, 215, or 1815 or an apparatussuch as one of the apparatuses 1115, 1215, 1315, or 1415 may execute oneor more sets of codes to control the functional elements of the UE orapparatus to perform the functions described below.

At block 2305, the method 2300 may include identifying an OFDMAconfiguration of an uplink channel for uplink communications (e.g.,LTE/LTE-A uplink communications) in an unlicensed radio frequencyspectrum band (e.g., a shared radio frequency spectrum band usable forWi-Fi and/or LTE/LTE-A communications). In some examples, the uplinkchannel for which the configuration is identified may include a PUSCH.In some examples, the uplink channel may include a UL-MIMO channel. Theoperation(s) at block 2305 may be performed using the wirelesscommunication management module 1120, 1220, 1320, 1420, and/or 1860described with reference to FIGS. 11, 12, 13, 14, and/or 18, the uplinkchannel configuration selector module 1240 described with reference toFIG. 12, and/or the uplink channel configuration identifier module 1340and/or 1440 described with reference to FIGS. 13 and/or 14.

At block 2310, the method 2300 may include generating an OFDMA waveformbased on the identified configuration. The operation(s) at block 2310may be performed using the wireless communication management module1120, 1220, 1320, 1420, and/or 1860 described with reference to FIGS.11, 12, 13, 14, and/or 18, and/or the waveform generator module 1245,1345, and/or 1445 described with reference to FIGS. 12, 13, and/or 14.

At block 2315, the method 2300 may include communicating (e.g.,transmitting) the generated OFDMA waveform in a signal in the unlicensedradio frequency spectrum band using the uplink channel. The operation(s)at block 2315 may be performed using the wireless communicationmanagement module 1120, 1220, 1320, 1420, and/or the communicationmanagement module 1860 described with reference to FIGS. 11, 12, 13, 14,and/or 18, the waveform communication module 1250, 1350, and/or 1450described with reference to FIGS. 12, 13, and/or 14, the transmittermodule 1130, 1230, 1330, and/or 1430 described with reference to FIGS.11, 12, 13, and/or 14, the unlicensed radio frequency spectrum bandtransmitter module 1234 and/or 1434 described with reference to FIGS. 12and/or 14, and/or the transceiver module(s) 1870 described withreference to FIG. 18.

The method 2300 may also include transmitting a DM-RS on the uplinkchannel, in a set of one or more time slots and one or more frequencysub-carriers. The DM-RS may be transmitted in conjunction withcommunicating the generated OFDMA waveform at block 2315.

In some examples, the set of one or more time slots and one or morefrequency sub-carriers in which the DM-RS is transmitted may be the sameas a set of one or more time slots and one or more frequencysub-carriers used to receive a UE-RS on a downlink channel (e.g., asdescribed with reference to FIG. 5 and FIG. 6). In other cases, the setof one or more time slots and one or more frequency sub-carriers inwhich the DM-RS is transmitted may differ in at least one respect from aset of one or more time slots and one or more frequency sub-carriersused to receive a UE-RS on a downlink channel (e.g., as described withreference to FIG. 5 and FIG. 7). The downlink channel may be a downlinkchannel used for downlink communications (e.g., LTE/LTE-A downlinkcommunications) in a licensed radio frequency spectrum band (e.g., anLTE/LTE-A radio frequency spectrum band usable for LTE/LTE-Acommunications) or the unlicensed radio frequency spectrum band.

The DM-RS transmission may be performed using the wireless communicationmanagement module 1120, 1220, 1320, 1420, and/or the communicationmanagement module 1860 described with reference to FIGS. 11, 12, 13, 14,and/or 18, the transmitter module 1130, 1230, 1330, and/or 1430described with reference to FIGS. 11, 12, 13, and/or 14, the datachannel module 1460 and/or the DM-RS module 1472 described withreference to FIG. 14, the unlicensed radio frequency spectrum bandtransmitter module 1234 and/or 1434 described with reference to FIGS. 12and/or 14, and/or the transceiver module(s) 1870 described withreference to FIG. 18.

Thus, the method 2300 may provide for wireless communication. It shouldbe noted that the method 2300 is just one implementation and that theoperations of the method 2300 may be rearranged or otherwise modifiedsuch that other implementations are possible.

FIG. 24 is a flowchart illustrating an example of a method 2400 ofwireless communication, in accordance with various aspects of thepresent disclosure. For clarity, the method 2400 is described below withreference to aspects of one or more of the UEs 115, 215, and/or 1815described with reference to FIGS. 1, 2A, 2B, and/or 18, and/or aspectsof one or more of the apparatuses 1115, 1215, 1315, and/or 1415described with reference to FIGS. 11, 12, 13, and/or 14. In someexamples, a UE such as one of the UEs 115, 215, or 1815 or an apparatussuch as one of the apparatuses 1115, 1215, 1315, or 1415 may execute oneor more sets of codes to control the functional elements of the UE orapparatus to perform the functions described below.

At block 2405, the method 2400 may include identifying an OFDMAconfiguration of an uplink channel for uplink communications (e.g.,LTE/LTE-A uplink communications) in an unlicensed radio frequencyspectrum band (e.g., a shared radio frequency spectrum band usable forWi-Fi and/or LTE/LTE-A communications). In some examples, the uplinkchannel for which the configuration is identified may include a PUCCH.In some examples, the uplink channel may include a UL-MIMO channel. Theoperation(s) at block 2405 may be performed using the wirelesscommunication management module 1120, 1220, 1320, 1420, and/or thecommunication management module 1860 described with reference to FIGS.11, 12, 13, 14, and/or 18, the uplink channel configuration selectormodule 1240 described with reference to FIG. 12, and/or the uplinkchannel configuration identifier module 1340 and/or 1440 described withreference to FIGS. 13 and/or 14.

At block 2410, the method 2400 may include generating an OFDMA waveformbased on the identified configuration. The operation(s) at block 2410may be performed using the wireless communication management module1120, 1220, 1320, 1420, and/or the communication management module 1860described with reference to FIGS. 11, 12, 13, 14, and/or 18, and/or thewaveform generator module 1245, 1345, and/or 1445 described withreference to FIGS. 12, 13, and/or 14.

Following the operation(s) at block 2410, the method 2400 may performthe operation(s) included in one or more of blocks 2415, 2420, and/or2425. At each of blocks 2415, 2420, and 2425, the method 2400 mayinclude communicating (e.g., transmitting) the generated OFDMA waveformin a signal in the unlicensed radio frequency spectrum band using theuplink channel.

At block 2415, the method 2400 may include transmitting duplicate copiesof the PUCCH in a plurality of interleaved resource blocks, asdescribed, for example, with reference to FIG. 8A. At block 2420, themethod 2400 may include transmitting the PUCCH within a plurality ofinterleaved resource blocks according to a code division multiplexingsequence or other orthogonal sequence, as also described, for example,with reference to FIG. 8A. At block 2425, the method 2400 may includemultiplexing the PUCCH within a plurality of resource elements of anenhanced resource element group, as described, for example, withreference to FIG. 8B.

The operation(s) at block 2415, 2420, and/or 2425 may be performed usingthe wireless communication management module 1120, 1220, 1320, 1420,and/or the communication management module 1860 described with referenceto FIGS. 11, 12, 13, 14, and/or 18, the waveform communication module1250, 1350, and/or 1450 described with reference to FIGS. 12, 13, and/or14, the control channel module 1480 described with reference to FIG. 14,the transmitter module 1130, 1230, 1330, and/or 1430 described withreference to FIGS. 11, 12, 13, and/or 14, the unlicensed radio frequencyspectrum band transmitter module 1234 and/or 1434 described withreference to FIGS. 12 and/or 14, and/or the transceiver module(s) 1870described with reference to FIG. 18.

Thus, the method 2400 may provide for wireless communication. It shouldbe noted that the method 2400 is just one implementation and that theoperations of the method 2400 may be rearranged or otherwise modifiedsuch that other implementations are possible.

FIG. 25 is a flowchart illustrating an example of a method 2500 ofwireless communication, in accordance with various aspects of thepresent disclosure. For clarity, the method 2500 is described below withreference to aspects of one or more of the UEs 115, 215, and/or 1815described with reference to FIGS. 1, 2A, 2B, and/or 18, and/or aspectsof one or more of the apparatuses 1115, 1215, 1315, and/or 1415described with reference to FIGS. 11, 12, 13, and/or 14. In someexamples, a UE such as one of the UEs 115, 215, or 1815 or an apparatussuch as one of the apparatuses 1115, 1215, 1315, or 1415 may execute oneor more sets of codes to control the functional elements of the UE orapparatus to perform the functions described below.

At block 2505, the method 2500 may include identifying an OFDMAconfiguration of an uplink channel for uplink communications (e.g.,LTE/LTE-A uplink communications) in an unlicensed radio frequencyspectrum band (e.g., a shared radio frequency spectrum band usable forWi-Fi and/or LTE/LTE-A communications). In some examples, the uplinkchannel for which the configuration is identified may include a PUCCH.In some examples, the uplink channel may include a UL-MIMO channel. Theoperation(s) at block 2505 may be performed using the wirelesscommunication management module 1120, 1220, 1320, 1420, and/or thecommunication management module 1860 described with reference to FIGS.11, 12, 13, 14, and/or 18, the uplink channel configuration selectormodule 1240 described with reference to FIG. 12, and/or the uplinkchannel configuration identifier module 1340 and/or 1440 described withreference to FIGS. 13 and/or 14.

At block 2510, the method 2500 may include generating an OFDMA waveformbased on the identified configuration. The operation(s) at block 2510may be performed using the wireless communication management module1120, 1220, 1320, 1420, and/or 1860 described with reference to FIGS.11, 12, 13, 14, and/or 18, and/or the waveform generator module 1245,1345, and/or 1445 described with reference to FIGS. 12, 13, and/or 14.

At block 2515, the method 2500 may include communicating (e.g.,transmitting) the generated OFDMA waveform in a signal in the unlicensedradio frequency spectrum band using the uplink channel. The operation(s)at block 2515 may be performed using the wireless communicationmanagement module 1120, 1220, 1320, 1420, and/or the communicationmanagement module 1860 described with reference to FIGS. 11, 12, 13, 14,and/or 18, the waveform communication module 1250, 1350, and/or 1450described with reference to FIGS. 12, 13, and/or 14, the transmittermodule 1130, 1230, 1330, and/or 1430 described with reference to FIGS.11, 12, 13, and/or 14, the unlicensed radio frequency spectrum bandtransmitter module 1234 and/or 1434 described with reference to FIGS. 12and/or 14, and/or the transceiver module(s) 1870 described withreference to FIG. 18.

In conjunction with communicating the generated OFDMA waveform at block2515, the method 2500 may perform the operation(s) included in one ormore of blocks 2520, 2525, and/or 2530.

At block 2520, the method 2500 may include transmitting an SRS on theuplink channel. The SRS may be located in an OFDM symbol of a subframethat is different from a last OFDM symbol of the subframe, as described,for example, with reference to FIG. 4. In other cases, the SRS may belocated in the last OFDM symbol of the subframe. The SRS may, in someexamples, be configured similarly to how SRS is configured for anLTE/LTE-A uplink channel in a licensed radio frequency spectrum band(e.g., the SRS may be Zadoff-Chu (ZC) sequence based).

At block 2525, the method 2500 may include transmitting a CSI-RS on theuplink channel. The CSI-RS may, in some examples, be transmittedindependent of an allocation of resources and on all resource blocks. Insome examples, the CSI-RS may be transmitted depending on a resourceallocation. The CSI-RS may be wideband and include N tones per resourceblock. The symbols used for CSI-RS may be pre-defined or defined throughcontrol channel (e.g., PUCCH) or radio resource control (RRC) signaling.A rate matching required for a PUSCH and a PUCCH, to accommodatetransmission of the CSI-RS, may be indicated to other UEs or apparatusesthat are frequency multiplexed on a same uplink subframe of the uplinkchannel. The method 2500 may also include transmitting a channel stateinformation interference measurement (CSI-IM) on the uplink channel.

At block 2530, the generated OFDMA waveform may be communicated withoutan SRS in the signal in the unlicensed radio frequency spectrum bandusing the uplink channel.

The operation(s) at block 2520, 2525, and/or 2530 may be performed usingthe wireless communication management module 1120, 1220, 1320, 1420,and/or the communication management module 1860 described with referenceto FIGS. 11, 12, 13, 14, and/or 18, the waveform communication module1250, 1350, and/or 1450 described with reference to FIGS. 12, 13, and/or14, the transmitter module 1130, 1230, 1330, and/or 1430 described withreference to FIGS. 11, 12, 13, and/or 14, the unlicensed radio frequencyspectrum band transmitter module 1234 and/or 1434 described withreference to FIGS. 12 and/or 14, and/or the transceiver module(s) 1870described with reference to FIG. 18. The operation(s) at block 2520 mayalso be perfumed using the SRS module 1485 described with reference toFIG. 14. The operation(s) at block 2525 may also be performed using theCSI-RS module 1490 described with reference to FIG. 14.

Thus, the method 2500 may provide for wireless communication. It shouldbe noted that the method 2500 is just one implementation and that theoperations of the method 2500 may be rearranged or otherwise modifiedsuch that other implementations are possible.

FIG. 26 is a flowchart illustrating an example of a method 2600 ofwireless communication, in accordance with various aspects of thepresent disclosure. For clarity, the method 2600 is described below withreference to aspects of one or more of the UEs 115, 215, and/or 1815described with reference to FIGS. 1, 2A, 2B, and/or 18, and/or aspectsof one or more of the apparatuses 1115, 1215, 1315, and/or 1415described with reference to FIGS. 11, 12, 13, and/or 14. In someexamples, a UE such as one of the UEs 115, 215, or 1815 or an apparatussuch as one of the apparatuses 1115, 1215, 1315, or 1415 may execute oneor more sets of codes to control the functional elements of the UE orapparatus to perform the functions described below.

At block 2605, the method 2600 may include identifying an OFDMAconfiguration of an uplink channel for uplink communications (e.g.,LTE/LTE-A uplink communications) in an unlicensed radio frequencyspectrum band (e.g., a shared radio frequency spectrum band usable forWi-Fi and/or LTE/LTE-A communications). The operation(s) at block 2605may be performed using the wireless communication management module1120, 1220, 1320, 1420, and/or the communication management module 1860described with reference to FIGS. 11, 12, 13, 14, and/or 18, the uplinkchannel configuration selector module 1240 described with reference toFIG. 12, and/or the uplink channel configuration identifier module 1340and/or 1440 described with reference to FIGS. 13 and/or 14.

In some examples, the uplink channel for which the configuration isidentified may include a PUSCH and/or a PUCCH. In some examples, theuplink channel may include a UL-MIMO channel.

At block 2610, the method 2600 may include generating an OFDMA waveformbased on the identified configuration. The operation(s) at block 2610may be performed using the wireless communication management module1120, 1220, 1320, 1420, and/or the communication management module 1860described with reference to FIGS. 11, 12, 13, 14, and/or 18, and/or thewaveform generator module 1245, 1345, and/or 1445 described withreference to FIGS. 12, 13, and/or 14.

At blocks 2615, 2620, 2625, 2630, 2635, 2640, and/or 2645, the method2600 may include communicating (e.g., transmitting) the generated OFDMAwaveform in a signal in the unlicensed radio frequency spectrum bandusing the uplink channel.

At block 2615, the method 2600 may include determining whether theuplink channel includes a PUCCH but not a PUSCH. If so, the method 2600may include using a first set of resource blocks to transmit the uplinkchannel at block 2620. Otherwise, the method 2600 may proceed to block2625.

At block 2625, the method 2600 may include determining whether theuplink channel includes the PUSCH but not the PUCCH. If so, the method2600 may include using a second set of resource blocks to transmit theuplink channel at block 2630. Otherwise, the method 2600 may proceed toblock 2635.

At block 2635, the method 2600 may include determining whether theuplink channel includes the PUCCH and the PUSCH. If so, the method 2600may include frequency division multiplexing the PUCCH and the PUSCH onthe uplink channel at block 2640. When frequency division multiplexingthe PUCCH and the PUSCH on the uplink channel, a subset of less than allof the first set of resource blocks may be used to transmit the PUCCH,and at least some of the second set of resource blocks may be used totransmit the PUSCH, as described, for example, with reference to FIG.10.

When it is determined at block 2635 that the uplink channel does notinclude PUCCH or PUSCH, the method 2600 may include transmitting anuplink channel that does not include PUCCH or PUSCH at block 2645.

The operation(s) at block 2615, 2620, 2625, 2630, 2635, 2640, and/or2645 may be performed using the wireless communication management module1120, 1220, 1320, 1420, and/or the communication management module 1860described with reference to FIGS. 11, 12, 13, 14, and/or 18, thewaveform communication module 1250, 1350, and/or 1450 described withreference to FIGS. 12, 13, and/or 14, the data channel module 1460, thecontrol channel module 1480, and/or the control and data multiplexingmodule 1495 described with reference to FIG. 14, the transmitter module1130, 1230, 1330, and/or 1430 described with reference to FIGS. 11, 12,13, and/or 14, the unlicensed radio frequency spectrum band transmittermodule 1234 and/or 1434 described with reference to FIGS. 12 and/or 14,and/or the transceiver module(s) 1870 described with reference to FIG.18.

Thus, the method 2600 may provide for wireless communication. It shouldbe noted that the method 2600 is just one implementation and that theoperations of the method 2600 may be rearranged or otherwise modifiedsuch that other implementations are possible.

FIG. 27 is a flowchart illustrating an example of a method 2700 ofwireless communication, in accordance with various aspects of thepresent disclosure. For clarity, the method 2700 is described below withreference to aspects of one or more of the UEs 115, 215, and/or 1815described with reference to FIGS. 1, 2A, 2B, and/or 18, and/or aspectsof one or more of the apparatuses 1115, 1215, 1315, and/or 1415described with reference to FIGS. 11, 12, 13, and/or 14. In someexamples, a UE such as one of the UEs 115, 215, or 1815 or an apparatussuch as one of the apparatuses 1115, 1215, 1315, or 1415 may execute oneor more sets of codes to control the functional elements of the UE orapparatus to perform the functions described below.

At block 2705, the method 2700 may include identifying an OFDMAconfiguration of an uplink channel for uplink communications (e.g.,LTE/LTE-A uplink communications) in an unlicensed radio frequencyspectrum band (e.g., a shared radio frequency spectrum band usable forWi-Fi and/or LTE/LTE-A communications). The operation(s) at block 2705may be performed using the wireless communication management module1120, 1220, 1320, 1420, and/or the communication management module 1860described with reference to FIGS. 11, 12, 13, 14, and/or 18, the uplinkchannel configuration selector module 1240 described with reference toFIG. 12, and/or the uplink channel configuration identifier module 1340and/or 1440 described with reference to FIGS. 13 and/or 14.

In some examples, the uplink channel for which the configuration isidentified may include a PUSCH and/or a PUCCH. In some examples, theuplink channel may include a UL-MIMO channel.

At block 2710, the method 2700 may include generating an OFDMA waveformbased on the identified configuration. The operation(s) at block 2710may be performed using the wireless communication management module1120, 1220, 1320, 1420, and/or the communication management module 1860described with reference to FIGS. 11, 12, 13, 14, and/or 18, and/or thewaveform generator module 1245, 1345, and/or 1445 described withreference to FIGS. 12, 13, and/or 14.

At blocks 2715, 2720, 2725, 2730, 2735, 2740, and/or 2745, the method2700 may include communicating (e.g., transmitting) the generated OFDMAwaveform in a signal in the unlicensed radio frequency spectrum bandusing the uplink channel.

At block 2715, the method 2700 may include determining whether theuplink channel includes a PUCCH but not a PUSCH. If so, the method 2700may include using a first set of resource blocks to transmit the uplinkchannel at block 2720. Otherwise, the method 2700 may proceed to block2725.

At block 2725, the method 2700 may include determining whether theuplink channel includes the PUSCH but not the PUCCH. If so, the method2700 may include using a second set of resource blocks to transmit theuplink channel at block 2730. Otherwise, the method 2700 may proceed toblock 2735.

At block 2735, the method 2700 may include determining whether theuplink channel includes the PUCCH and the PUSCH. If so, the method 2700may include frequency division multiplexing the PUCCH and the PUSCH bypuncturing at least one frequency sub-carrier of at least one resourceblock of the first set of resource blocks, at block 2740, to transmit atleast part of the PUSCH.

When it is determined at block 2735 that the uplink channel does notinclude PUCCH or PUSCH, the method 2700 may include transmitting anuplink channel that does not include PUCCH or PUSCH.

The operation(s) at block 2715, 2720, 2725, 2730, 2735, 2740, and/or2745 may be performed using the wireless communication management module1120, 1220, 1320, 1420, and/or the communication management module 1860described with reference to FIGS. 11, 12, 13, 14, and/or 18, thewaveform communication module 1250, 1350, and/or 1450 described withreference to FIGS. 12, 13, and/or 14, the data channel module 1460, thecontrol channel module 1480, and/or the control and data multiplexingmodule 1495 described with reference to FIG. 14, the transmitter module1130, 1230, 1330, and/or 1430 described with reference to FIGS. 11, 12,13, and/or 14, the unlicensed radio frequency spectrum band transmittermodule 1234 and/or 1434 described with reference to FIGS. 12 and/or 14,and/or the transceiver module(s) 1870 described with reference to FIG.18.

Thus, the method 2700 may provide for wireless communication. It shouldbe noted that the method 2700 is just one implementation and that theoperations of the method 2700 may be rearranged or otherwise modifiedsuch that other implementations are possible.

When transmitting a PUCCH on an uplink channel for uplink communicationsin an unlicensed radio frequency spectrum band, as described, forexample, with reference to FIGS. 24, 26, and/or 27, acknowledgementspertaining to a PDSCH may be transmitted as part of the PUCCH. Whentransmitting a PUSCH on an uplink channel for uplink communications inan unlicensed radio frequency spectrum band, as described, for example,with reference to FIGS. 22, 23, 26, and/or 27, CQI pertaining to a PDSCHmay be transmitted as part of the PUSCH. In cases where a PUCCH and aPUSCH are frequency division multiplexed on an uplink channel,acknowledgements pertaining to a PDSCH may be transmitted as part of thePUCCH, and CQI for the PDSCH may be transmitted as part of the PUSCH.

FIG. 28 is a flowchart illustrating an example of a method 2800 ofwireless communication, in accordance with various aspects of thepresent disclosure. For clarity, the method 2800 is described below withreference to aspects of one or more of the UEs 115, 215, and/or 1815described with reference to FIGS. 1, 2A, 2B, and/or 18, aspects of oneor more of the base stations 105, 205, and/or 1705 described withreference to FIGS. 1, 2A, 2B, and/or 17, and/or aspects of one or moreof the apparatuses 1115, 1515, and/or 1615 described with reference toFIGS. 11, 15, and/or 16. In some examples, a UE such as one of the UEs115, 215, or 1815, or a base station such as one of the base stations105, 205, or 1705, or an apparatus such as one of the apparatuses 1115,1515, or 1615 may execute one or more sets of codes to control thefunctional elements of the UE, base station, or apparatus to perform thefunctions described below.

At block 2805, the method 2800 may include associating a virtual cellidentifier of a first base station with transmissions between the firstbase station and a first UE. The virtual cell identifier may also beassociated with transmissions between a second base station and a secondUE. The transmissions between the first base station and the first UE,and between the second base station and the second UE, may, in someexamples, be communications (e.g., LTE/LTE-A communications) in anunlicensed radio frequency spectrum band (e.g., a shared radio frequencyspectrum band usable for Wi-Fi and/or LTE/LTE-A communications). Theoperation(s) at block 2805 may be performed using the wirelesscommunication management module 1120, 1520, 1620, and/or thecommunication management module 1860 described with reference to FIGS.11, 15, 16, and/or 18, and/or the virtual cell identifier associationmodule 1540 and/or 1640 described with reference to FIGS. 15 and/or 16.

At block 2810, the method 2800 may include identifying a set of commonresource blocks for transmission of a DM-RS in an uplink channel and adownlink channel between the first base station and the first UE. Theidentification of the set of common resource blocks may be based atleast in part on the virtual cell identifier associated withtransmissions between the first base station and the first UE at block2805. The operation(s) at block 2810 may be performed using the wirelesscommunication management module 1120, 1520, 1620, and/or thecommunication management module 1860 described with reference to FIGS.11, 15, 16, and/or 18, and/or the common resource block identifiermodule 1545 and/or 1645 described with reference to FIGS. 15 and/or 16.

The operation(s) at block 2805 and 2810 may be performed by a UE, by abase station, or by another apparatus.

Thus, the method 2800 may provide for wireless communication. It shouldbe noted that the method 2800 is just one implementation and that theoperations of the method 2800 may be rearranged or otherwise modifiedsuch that other implementations are possible.

FIG. 29 is a flowchart illustrating an example of a method 2900 ofwireless communication, in accordance with various aspects of thepresent disclosure. For clarity, the method 2900 is described below withreference to aspects of one or more of the UEs 115, 215, and/or 1815described with reference to FIGS. 1, 2A, 2B, and/or 18, aspects of oneor more of the base stations 105, 205, and/or 1705 described withreference to FIGS. 1, 2A, 2B, and/or 17, and/or aspects of one or moreof the apparatuses 1115, 1515, and/or 1615 described with reference toFIGS. 11, 15, and/or 16. In some examples, a UE such as one of the UEs115, 215, or 1815, or a base station such as one of the base stations105, 205, or 1705, or an apparatus such as one of the apparatuses 1115,1515, or 1615 may execute one or more sets of codes to control thefunctional elements of the UE, base station, or apparatus to perform thefunctions described below.

At block 2905, the method 2900 may include associating a virtual cellidentifier of a first base station with transmissions between the firstbase station and a first UE. The virtual cell identifier may also beassociated with transmissions between a second base station and a secondUE. The transmissions between the first base station and the first, andbetween the second base station and the second UE, may, in someexamples, be communications (e.g., LTE/LTE-A communications) in anunlicensed radio frequency spectrum band (e.g., a shared radio frequencyspectrum band usable for Wi-Fi and/or LTE/LTE-A communications). Theoperation(s) at block 2905 may be performed using the wirelesscommunication management module 1120, 1520, 1620, and/or thecommunication management module 1860 described with reference to FIGS.11, 15, 16, and/or 18, and/or the virtual cell identifier associationmodule 1540 and/or 1640 described with reference to FIGS. 15 and/or 16.

At block 2910, the method 2900 may include identifying a set of commonresource blocks for transmission of a DM-RS in an uplink channel and adownlink channel between the first base station and the first UE. Theidentification of the set of common resource blocks may be based atleast in part on the virtual cell identifier associated withtransmissions between the first base station and the first UE at block2905. The operation(s) at block 2910 may be performed using the wirelesscommunication management module 1120, 1520, 1620, and/or thecommunication management module 1860 described with reference to FIGS.11, 15, 16, and/or 18, and/or the common resource block identifiermodule 1545 and/or 1645 described with reference to FIGS. 15 and/or 16.

At block 2915, the method 2900 may include associating a first linkidentifier with the uplink channel between the first base station andthe first UE, and associating a second link identifier with the downlinkchannel between the first base station and the first UE, where the firstlink identifier is different from the second link identifier. Theoperation(s) at block 2915 may be performed using the wirelesscommunication management module 1120, 1520, 1620, and/or thecommunication management module 1860 described with reference to FIGS.11, 15, 16, and/or 18, and/or the link identifier association module1650 described with reference to FIG. 16.

At block 2920, the method 2900 may include identifying a port associatedwith a first spatial multiplexing for transmission of the DM-RS betweenthe first base station and the first UE. The first spatial multiplexingmay be different from a second spatial multiplexing associated with aport used to transmit a DM-RS between the second base station and thesecond UE. The operation(s) at block 2920 may be performed using thewireless communication management module 1120, 1520, 1620, and/or thecommunication management module 1860 described with reference to FIGS.11, 15, 16, and/or 18, and/or the DM-RS port identification module 1655described with reference to FIG. 16.

At block 2925, the method 2900 may include transmitting the first linkidentifier with transmissions in the uplink channel or transmitting thesecond link identifier with transmissions in the downlink channel. Thetransmissions may be made via the identified port. In some examples,transmitting the first link identifier with transmissions in the uplinkchannel may include generating the DM-RS as a function of the first linkidentifier. In other cases, transmitting the second link identifier withtransmissions in the downlink channel may include generating the DM-RSas a function of the second link identifier.

The operation(s) at block 2925 may be performed using the wirelesscommunication management module 1120, 1520, 1620, and/or thecommunication management module 1860 described with reference to FIGS.11, 15, 16, and/or 18, the waveform communication module 1660 describedwith reference to FIG. 16, the transmitter module 1130, 1530, and/or1630 described with reference to FIGS. 11, 15, and/or 16, the unlicensedradio frequency spectrum band transmitter module 1534 and/or 1634described with reference to FIGS. 15 and/or 16, and/or the transceivermodule(s) 1870 described with reference to FIG. 18.

The operation(s) at block 2905, 2910, 2915, 2920, and 2925 may beperformed by a UE, by a base station, or by another apparatus.

Thus, the method 2900 may provide for wireless communication. It shouldbe noted that the method 2900 is just one implementation and that theoperations of the method 2900 may be rearranged or otherwise modifiedsuch that other implementations are possible.

In some examples, one or more aspects of the methods 1900, 2000, 2100,2200, 2300, 2400, 2500, 2600, 2700, 2800, and/or 2900 may be combined.

The detailed description set forth above in connection with the appendeddrawings describes examples and does not represent the only examplesthat may be implemented or that are within the scope of the claims. Theterms “example” and “exemplary,” when used in this description, mean“serving as an example, instance, or illustration,” and not “preferred”or “advantageous over other examples.” The detailed description includesspecific details for the purpose of providing an understanding of thedescribed techniques. These techniques, however, may be practicedwithout these specific details. In some instances, well-known structuresand apparatuses are shown in block diagram form in order to avoidobscuring the concepts of the described examples.

Information and signals may be represented using any of a variety ofdifferent technologies and techniques. For example, data, instructions,commands, information, signals, bits, symbols, and chips that may bereferenced throughout the above description may be represented byvoltages, currents, electromagnetic waves, magnetic fields or particles,optical fields or particles, or any combination thereof.

The various illustrative blocks and modules described in connection withthe disclosure herein may be implemented or performed with ageneral-purpose processor, a digital signal processor (DSP), an ASIC, anFPGA or other programmable logic device, discrete gate or transistorlogic, discrete hardware components, or any combination thereof designedto perform the functions described herein. A general-purpose processormay be a microprocessor, but in the alternative, the processor may beany conventional processor, controller, microcontroller, or statemachine. A processor may also be implemented as a combination ofcomputing devices, e.g., a combination of a DSP and a microprocessor,multiple microprocessors, one or more microprocessors in conjunctionwith a DSP core, or any other such configuration.

The functions described herein may be implemented in hardware, softwareexecuted by a processor, firmware, or any combination thereof. Ifimplemented in software executed by a processor, the functions may bestored on or transmitted over as one or more instructions or code on acomputer-readable medium. Other examples and implementations are withinthe scope and spirit of the disclosure and appended claims. For example,due to the nature of software, functions described above can beimplemented using software executed by a processor, hardware, firmware,hardwiring, or combinations of any of these. Features implementingfunctions may also be physically located at various positions, includingbeing distributed such that portions of functions are implemented atdifferent physical locations. Also, as used herein, including in theclaims, “or” as used in a list of items prefaced by “at least one of”indicates a disjunctive list such that, for example, a list of “at leastone of A, B, or C” means A or B or C or AB or AC or BC or ABC (i.e., Aand B and C).

Computer-readable media includes both computer storage media andcommunication media including any medium that facilitates transfer of acomputer program from one place to another. A storage medium may be anyavailable medium that can be accessed by a general purpose or specialpurpose computer. By way of example, and not limitation,computer-readable media can comprise RAM, ROM, EEPROM, CD-ROM or otheroptical disk storage, magnetic disk storage or other magnetic storagedevices, or any other medium that can be used to carry or store desiredprogram code means in the form of instructions or data structures andthat can be accessed by a general-purpose or special-purpose computer,or a general-purpose or special-purpose processor. Also, any connectionis properly termed a computer-readable medium. For example, if thesoftware is transmitted from a website, server, or other remote sourceusing a coaxial cable, fiber optic cable, twisted pair, digitalsubscriber line (DSL), or wireless technologies such as infrared, radio,and microwave, then the coaxial cable, fiber optic cable, twisted pair,DSL, or wireless technologies such as infrared, radio, and microwave areincluded in the definition of medium. Disk and disc, as used herein,include compact disc (CD), laser disc, optical disc, digital versatiledisc (DVD), floppy disk and Blu-ray disc where disks usually reproducedata magnetically, while discs reproduce data optically with lasers.Combinations of the above are also included within the scope ofcomputer-readable media.

The previous description of the disclosure is provided to enable aperson skilled in the art to make or use the disclosure. Variousmodifications to the disclosure will be readily apparent to thoseskilled in the art, and the generic principles defined herein may beapplied to other variations without departing from the spirit or scopeof the disclosure. Throughout this disclosure the term “example” or“exemplary” indicates an example or instance and does not imply orrequire any preference for the noted example. Thus, the disclosure isnot to be limited to the examples and designs described herein but is tobe accorded the widest scope consistent with the principles and novelfeatures disclosed herein.

What is claimed is:
 1. A method for wireless communication, comprising:identifying an orthogonal frequency-division multiple access (OFDMA)configuration of an uplink channel for uplink communications in anunlicensed radio frequency spectrum band; generating an OFDMA waveformbased on the identified OFDMA configuration; and communicating thegenerated OFDMA waveform in a signal in the unlicensed radio frequencyspectrum band using the uplink channel.
 2. The method of claim 1,wherein the uplink channel comprises a Physical Uplink Shared Channel(PUSCH).
 3. The method of claim 2, further comprising: allocatingresources for the PUSCH based at least in part on a bitmap of interlacesor resource blocks.
 4. The method of claim 2, further comprising:allocating resources for the PUSCH based at least in part on a startingresource block and a number of resource blocks or a starting interlaceand a number of interlaces, wherein an interlace is a pre-defined set ofresource blocks selected to span an entire bandwidth.
 5. The method ofclaim 4, wherein allocating the resources for the PUSCH is formulti-cluster transmission, wherein allocating the resources for thePUSCH is based in part on two or more of the resource blocks assigned toa user equipment.
 6. The method of claim 2, further comprising: mappingone or more modulation symbols to one or more resource elementsaccording to one or more OFDM symbol positions.
 7. The method of claim2, further comprising: mapping one or more modulation symbols to one ormore resource elements according to one or more frequency sub-carriers.8. The method of claim 2, further comprising: mapping one or moremodulation symbols to one or more resource elements according to aninterleaving of time slots and frequency sub-carriers.
 9. The method ofclaim 2, further comprising: transmitting a demodulation referencesignal (DM-RS) on the uplink channel in a first set of one or more timeslots and one or more first frequency sub-carriers, wherein the firstset of one or more time slots and one or more first frequencysub-carriers are the same as a second set of one or more time slots andone or more second frequency sub-carriers used to receive a userequipment specific reference signal (UE-RS) on a downlink channel. 10.The method of claim 2, further comprising: transmitting a demodulationreference signal (DM-RS) on the uplink channel in a first set of one ormore time slots and one or more first frequency sub-carriers, whereinthe first set of one or more time slots and one or more first frequencysub-carriers differs in at least one respect from a second set of one ormore time slots and one or more second frequency sub-carriers used toreceive a user equipment specific reference signal (UE-RS) on a downlinkchannel.
 11. The method of claim 1, further comprising: using physicalresource block (PRB) bundling when generating the OFDMA waveform basedon the identified OFDMA configuration.
 12. The method of claim 1,further comprising: using precoder cycling when generating the OFDMAwaveform based on the identified OFDMA configuration, wherein a precoderis cycled through a pre-defined set of precoders, and wherein theprecoder is indicated by a base station as part of an uplink grant. 13.The method of claim 12, wherein the precoder is derived by a UE based atleast in part on downlink channel state information reference signal(CSI-RS) transmissions.
 14. The method of claim 1, wherein the uplinkchannel comprises an uplink multiple-input multiple-output (UL-MIMO)channel or a multi-user MIMO (MU-MIMO) channel.
 15. The method of claim1, further comprising: applying symbol permutation or phase rotation toreduce a metric indicating symbol power when generating the OFDMAwaveform based on the identified OFDMA configuration.
 16. The method ofclaim 1, further comprising: applying different scrambling sequences tothe OFDMA waveform; and selecting one of the scrambling sequences foruse when communicating the generated OFDMA waveform in the signal in theunlicensed radio frequency spectrum band.
 17. The method of claim 1,wherein the uplink channel comprises a Physical Uplink Control Channel(PUCCH).
 18. The method of claim 17, wherein communicating the generatedOFDMA waveform in a signal in the unlicensed radio frequency spectrumband using the uplink channel comprises: transmitting duplicate copiesof the PUCCH in a plurality of interleaved resource blocks.
 19. Themethod of claim 17, wherein communicating the generated OFDMA waveformin a signal in the unlicensed radio frequency spectrum band using theuplink channel comprises: multiplexing the PUCCH within a plurality ofinterleaved resource blocks according to a code division multiplexingsequence or other orthogonal sequence.
 20. The method of claim 17,wherein communicating the generated OFDMA waveform in a signal in theunlicensed radio frequency spectrum band using the uplink channelcomprises: multiplexing the PUCCH within a plurality of resourceelements of an enhanced resource element group.
 21. The method of claim1, wherein the uplink channel comprises a Physical Random Access Channel(PRACH) transmitted on one or more pre-allocated interlaces.
 22. Themethod of claim 1, further comprising: transmitting a sounding referencesignal (SRS) on the uplink channel, the SRS being located in an OFDMsymbol position of a subframe that is different from a last OFDM symbolposition of the subframe.
 23. The method of claim 1, further comprising:transmitting a channel state information reference signal (CSI-RS) inthe uplink channel, independent of an allocation of resources and on allresource blocks or depending on a resource allocation.
 24. The method ofclaim 23, further comprising: generating, by a base station, a precoderto be used in a downlink channel based at least in part on the uplinkCSI-RS transmission.
 25. The method of claim 23, further comprising:indicating a rate matching for a Physical Uplink Shared Channel (PUSCH)and a Physical Uplink Control Channel (PUCCH) to accommodatetransmission of the CSI-RS.
 26. The method of claim 23, furthercomprising: transmitting a channel state information interferencemeasurement (CSI-IM) in the uplink channel.
 27. The method of claim 1,further comprising: communicating the generated OFDMA waveform without asounding reference signal (SRS) in the signal in the unlicensed radiofrequency spectrum band using the uplink channel.
 28. The method ofclaim 1, further comprising: using a first set of resource blocks totransmit the uplink channel when the uplink channel comprises a PhysicalUplink Control Channel (PUCCH) but not a Physical Uplink Shared Channel(PUSCH); and using a second set of resource blocks to transmit theuplink channel when the uplink channel comprises the PUSCH but not thePUCCH, the second set of resource blocks being different than the firstset of resource blocks.
 29. The method of claim 28, further comprising:when the uplink channel comprises the PUCCH and the PUSCH, frequencydivision multiplexing the PUCCH and the PUSCH on the uplink channel and,using a subset of less than all of the first set of resource blocks totransmit the PUCCH; and using at least some of the second set ofresource blocks to transmit the PUSCH.
 30. The method of claim 29,further comprising: when the PUCCH and the PUSCH are frequency divisionmultiplexed, also using at least one of the first set of resource blocksto transmit the PUSCH.
 31. The method of claim 28, further comprising:when the uplink channel comprises the PUCCH and the PUSCH, frequencydivision multiplexing the PUCCH and the PUSCH by puncturing at least onefrequency sub-carrier of at least one resource block of the first set ofresource blocks to transmit at least part of the PUSCH.
 32. The methodof claim 1, further comprising; frequency division multiplexing aPhysical Uplink Control Channel (PUCCH) and a Physical Uplink SharedChannel (PUSCH) on the uplink channel; transmitting acknowledgementspertaining to a Physical Downlink Shared Channel (PDSCH) as part of thePUCCH; and transmitting channel quality information (CQI) of a pluralityof downlink carriers simultaneously as part of the PUSCH.
 33. The methodof claim 1, further comprising: receiving signaling from a base station;and selecting the OFDMA configuration of the uplink channel based atleast in part on the received signaling.
 34. The method of claim 33,wherein the signaling from the base station indicates a resource blockallocation, and wherein the OFDMA configuration of the uplink channel isselected based at least in part on the resource block allocation. 35.The method of claim 33, wherein the OFDMA configuration of the uplinkchannel is selected based at least in part on a modulation and codingscheme (MCS) indicated in a downlink grant or whether an uplinkmultiple-input multiple-output (UL-MIMO)/multi-user MIMO (MU-MIMO) isenabled or disabled.
 36. An apparatus for wireless communication,comprising: means for identifying an orthogonal frequency-divisionmultiple access (OFDMA) configuration of an uplink channel for uplinkcommunications in an unlicensed radio frequency spectrum band; means forgenerating an OFDMA waveform based on the identified OFDMAconfiguration; and means for communicating the generated OFDMA waveformin a signal in the unlicensed radio frequency spectrum band using theuplink channel.
 37. The apparatus of claim 36, wherein the uplinkchannel comprises a Physical Uplink Shared Channel (PUSCH).
 38. Theapparatus of claim 37, further comprising: means for allocatingresources for the PUSCH based at least in part on a bitmap of interlacesor resource blocks.
 39. The apparatus of claim 37, further comprising:means for allocating resources for the PUSCH based at least in part on astarting resource block and a number of resource blocks or a startinginterlace and a number of interlaces, wherein an interlace is apre-defined set of resource blocks selected to span an entire bandwidth.40. The apparatus of claim 39, wherein allocating the resources for thePUSCH is for multi-cluster transmission, wherein allocating theresources for the PUSCH is based in part on two or more of the resourceblocks assigned to a user equipment.
 41. The apparatus of claim 37,further comprising: means for mapping one or more modulation symbols toone or more resource elements according to one or more OFDM symbolpositions.
 42. The apparatus of claim 37, further comprising: means formapping one or more modulation symbols to one or more resource elementsaccording to one or more frequency sub-carriers.
 43. The apparatus ofclaim 37, further comprising: means for mapping one or more modulationsymbols to one or more resource elements according to an interleaving oftime slots and frequency sub-carriers.
 44. The apparatus of claim 37,further comprising: means for transmitting a demodulation referencesignal (DM-RS) on the uplink channel in a first set of one or more timeslots and one or more first frequency sub-carriers, wherein the firstset of one or more time slots and one or more first frequencysub-carriers are the same as a second set of one or more time slots andone or more second frequency sub-carriers used to receive a userequipment specific reference signal (UE-RS) on a downlink channel. 45.The apparatus of claim 37, further comprising: means for transmitting ademodulation reference signal (DM-RS) on the uplink channel in a firstset of one or more time slots and one or more first frequencysub-carriers, wherein the first set of one or more time slots and one ormore first frequency sub-carriers differs in at least one respect from asecond set of one or more time slots and one or more second frequencysub-carriers used to receive a user equipment specific reference signal(UE-RS) on a downlink channel.
 46. The apparatus of claim 36, furthercomprising: means for using physical resource block (PRB) bundling whengenerating the OFDMA waveform based on the identified OFDMAconfiguration.
 47. The apparatus of claim 36, further comprising: meansfor using precoder cycling when generating the OFDMA waveform based onthe identified OFDMA configuration, wherein a precoder is cycled througha pre-defined set of precoders, and wherein the precoder is indicated bya base station as part of an uplink grant.
 48. The apparatus of claim47, wherein the precoder is derived by a UE based at least in part ondownlink channel state information reference signal (CSI-RS)transmissions.
 49. The apparatus of claim 36, wherein the uplink channelcomprises an uplink multiple-input multiple-output (UL-MIMO) channel ora multi-user MIMO (MU-MIMO) channel.
 50. The apparatus of claim 36,further comprising: means for applying symbol permutation or phaserotation to reduce a metric indicating symbol power when generating theOFDMA waveform based on the identified OFDMA configuration.
 51. Theapparatus of claim 36, further comprising: means for applying differentscrambling sequences to the OFDMA waveform; and means for selecting oneof the scrambling sequences for use when communicating the generatedOFDMA waveform in the signal in the unlicensed radio frequency spectrumband.
 52. The apparatus of claim 36, wherein the uplink channelcomprises a Physical Uplink Control Channel (PUCCH).
 53. The apparatusof claim 52, wherein the means for communicating the generated OFDMAwaveform in a signal in the unlicensed radio frequency spectrum bandusing the uplink channel comprises: transmitting duplicate copies of thePUCCH in a plurality of interleaved resource blocks.
 54. The apparatusof claim 52, wherein communicating the generated OFDMA waveform in asignal in the unlicensed radio frequency spectrum band using the uplinkchannel comprises: multiplexing the PUCCH within a plurality ofinterleaved resource blocks according to a code division multiplexingsequence or other orthogonal sequence.
 55. The apparatus of claim 52,wherein communicating the generated OFDMA waveform in a signal in theunlicensed radio frequency spectrum band using the uplink channelcomprises: means for multiplexing the PUCCH within a plurality ofresource elements of an enhanced resource element group.
 56. Theapparatus of claim 36, wherein the uplink channel comprises a PhysicalRandom Access Channel (PRACH) transmitted on one or more pre-allocatedinterlaces.
 57. The apparatus of claim 36, further comprising: means fortransmitting a sounding reference signal (SRS) on the uplink channel,the SRS being located in an OFDM symbol position of a subframe that isdifferent from a last OFDM symbol position of the subframe.
 58. Theapparatus of claim 36, further comprising: means for transmitting achannel state information reference signal (CSI-RS) in the uplinkchannel, independent of an allocation of resources and on all resourceblocks or depending on a resource allocation.
 59. The apparatus of claim58, further comprising: generating, by a base station, a precoder to beused in a downlink channel based in part on the uplink CSI-RStransmission.
 60. The apparatus of claim 58, further comprising: meansfor indicating a rate matching for a Physical Uplink Shared Channel(PUSCH) and a Physical Uplink Control Channel (PUCCH) to accommodatetransmission of the CSI-RS.
 61. The apparatus of claim 58, furthercomprising: means for transmitting a channel state informationinterference measurement (CSI-IM) in the uplink channel.
 62. Theapparatus of claim 36, further comprising: means for communicating thegenerated OFDMA waveform without a sounding reference signal (SRS) inthe signal in the unlicensed radio frequency spectrum band using theuplink channel.
 63. The apparatus of claim 36, further comprising: meansfor using a first set of resource blocks to transmit the uplink channelwhen the uplink channel comprises a Physical Uplink Control Channel(PUCCH) but not a Physical Uplink Shared Channel (PUSCH); and means forusing a second set of resource blocks to transmit the uplink channelwhen the uplink channel comprises the PUSCH but not the PUCCH, thesecond set of resource blocks being different than the first set ofresource blocks.
 64. The apparatus of claim 63, further comprising:means for, when the uplink channel comprises the PUCCH and the PUSCH,frequency division multiplexing the PUCCH and the PUSCH on the uplinkchannel and, using a subset of less than all of the first set ofresource blocks to transmit the PUCCH; and using at least some of thesecond set of resource blocks to transmit the PUSCH.
 65. The apparatusof claim 64, further comprising: means for when the PUCCH and the PUSCHare frequency division multiplexed, also using at least one of the firstset of resource blocks to transmit the PUSCH.
 66. The apparatus of claim63, further comprising: means for, when the uplink channel comprises thePUCCH and the PUSCH, frequency division multiplexing the PUCCH and thePUSCH by puncturing at least one frequency sub-carrier of at least oneresource block of the first set of resource blocks to transmit at leastpart of the PUSCH.
 67. The apparatus of claim 36, further comprising;means for frequency division multiplexing a Physical Uplink ControlChannel (PUCCH) and a Physical Uplink Shared Channel (PUSCH) on theuplink channel; means for transmitting acknowledgements pertaining to aPhysical Downlink Shared Channel (PDSCH) as part of the PUCCH; and meansfor transmitting channel quality information (CQI) of a plurality ofdownlink carriers simultaneously as part of the PUSCH.
 68. The apparatusof claim 36, further comprising: means for receiving signaling from abase station; and means for selecting the OFDMA configuration of theuplink channel based at least in part on the received signaling.
 69. Theapparatus of claim 68, wherein the signaling from the base stationindicates a resource block allocation, and wherein the OFDMAconfiguration of the uplink channel is selected based at least in parton the resource block allocation.
 70. The apparatus of claim 68, whereinthe OFDMA configuration of the uplink channel is selected based at leastin part on a modulation and coding scheme (MCS) indicated in a downlinkgrant or whether an uplink multiple-input multiple-output(UL-MIMO)/multi-user MIMO (MU-MIMO) is enabled or disabled.
 71. Anapparatus for wireless communication, comprising: a processor; memory inelectronic communication with the processor; and instructions stored inthe memory, the instructions being executable by the processor to:identify an orthogonal frequency-division multiple access (OFDMA)configuration of an uplink channel for uplink communications in anunlicensed radio frequency spectrum band; generate an OFDMA waveformbased on the identified OFDMA configuration; and communicate thegenerated OFDMA waveform in a signal in the unlicensed radio frequencyspectrum band using the uplink channel.
 72. The apparatus of claim 71,wherein the uplink channel comprises a Physical Uplink Shared Channel(PUSCH).
 73. The apparatus of claim 72, wherein the instructions areexecutable by the processor to: transmit a demodulation reference signal(DM-RS) on the uplink channel in a first set of one or more time slotsand one or more first frequency sub-carriers, wherein the first set ofone or more time slots and one or more first frequency sub-carriers arethe same as a second set of one or more time slots and one or moresecond frequency sub-carriers used to receive a user equipment specificreference signal (UE-RS) on a downlink channel.
 74. The apparatus ofclaim 71, wherein the instructions are executable by the processor to:apply symbol permutation or phase rotation to reduce a metric indicatingsymbol power when generating the OFDMA waveform based on the identifiedOFDMA configuration.
 75. The apparatus of claim 71, wherein theinstructions are executable by the processor to: apply differentscrambling sequences to the OFDMA waveform; and select one of thescrambling sequences for use when communicating the generated OFDMAwaveform in the signal in the unlicensed radio frequency spectrum band.76. The apparatus of claim 71, wherein the uplink channel comprises aPhysical Uplink Control Channel (PUCCH).
 77. The apparatus of claim 76,wherein the instructions executable by the processor to communicate thegenerated OFDMA waveform in a signal in the unlicensed radio frequencyspectrum band using the uplink channel comprise instructions executableby the processor to: transmit duplicate copies of the PUCCH in aplurality of interleaved resource blocks.
 78. The apparatus of claim 76,wherein the instructions executable by the processor to communicate thegenerated OFDMA waveform in a signal in the unlicensed radio frequencyspectrum band using the uplink channel comprise instructions executableby the processor to: multiplex the PUCCH within a plurality ofinterleaved resource blocks according to a code division multiplexingsequence or other orthogonal sequence.
 79. The apparatus of claim 76,wherein the instructions executable to communicate the generated OFDMAwaveform in a signal in the unlicensed radio frequency spectrum bandusing the uplink channel comprise instructions executable by theprocessor to: multiplex the PUCCH within a plurality of resourceelements of an enhanced resource element group.
 80. The apparatus ofclaim 71, wherein the instructions are executable by the processor to:transmit a channel state information reference signal (CSI-RS) in theuplink channel, independent of an allocation of resources and on allresource blocks or depending on a resource allocation.
 81. The apparatusof claim 71, wherein the instructions are executable by the processorto: use a first set of resource blocks to transmit the uplink channelwhen the uplink channel comprises a Physical Uplink Control Channel(PUCCH) but not a Physical Uplink Shared Channel (PUSCH); and use asecond set of resource blocks to transmit the uplink channel when theuplink channel comprises the PUSCH but not the PUCCH, the second set ofresource blocks being different than the first set of resource blocks.82. The apparatus of claim 81, wherein the instructions are executableby the processor to: when the uplink channel comprises the PUCCH and thePUSCH, frequency division multiplex the PUCCH and the PUSCH on theuplink channel and, use a subset of less than all of the first set ofresource blocks to transmit the PUCCH; and use at least some of thesecond set of resource blocks to transmit the PUSCH.
 83. The apparatusof claim 82, wherein the instructions are executable by the processorto: when the PUCCH and the PUSCH are frequency division multiplexed,also use at least one of the first set of resource blocks to transmitthe PUSCH.
 84. The apparatus of claim 81, wherein the instructions areexecutable by the processor to: when the uplink channel comprises thePUCCH and the PUSCH, frequency division multiplex the PUCCH and thePUSCH by puncturing at least one frequency sub-carrier of at least oneresource block of the first set of resource blocks to transmit at leastpart of the PUSCH.
 85. The apparatus of claim 71, wherein theinstructions are executable by the processor to: frequency divisionmultiplex a Physical Uplink Control Channel (PUCCH) and a PhysicalUplink Shared Channel (PUSCH) on the uplink channel; transmitacknowledgements pertaining to a Physical Downlink Shared Channel(PDSCH) as part of the PUCCH; and transmitting channel qualityinformation (CQI) of a plurality of downlink carriers simultaneously aspart of the PUSCH.
 86. A non-transitory computer-readable medium storingcomputer-executable code for wireless communications, the codeexecutable by a processor to: identify an orthogonal frequency-divisionmultiple access (OFDMA) configuration of an uplink channel for uplinkcommunications in an unlicensed radio frequency spectrum band; generatean OFDMA waveform based on the identified OFDMA configuration; andcommunicate the generated OFDMA waveform in a signal in the unlicensedradio frequency spectrum band using the uplink channel.
 87. Thecomputer-readable medium of claim 86, wherein the uplink channelcomprises a Physical Uplink Shared Channel (PUSCH).
 88. Thecomputer-readable medium of claim 87, wherein the code is executable bythe processor to: transmit a demodulation reference signal (DM-RS) onthe uplink channel in a first set of one or more time slots and one ormore first frequency sub-carriers, wherein the first set of one or moretime slots and one or more first frequency sub-carriers are the same asa second set of one or more time slots and one or more second frequencysub-carriers used to receive a user equipment specific reference signal(UE-RS) on a downlink channel.
 89. The computer-readable medium of claim86, wherein the code is executable by the processor to: transmit achannel state information reference signal (CSI-RS) in the uplinkchannel, independent of an allocation of resources and on all resourceblocks or depending on a resource allocation.
 90. The computer-readablemedium of claim 86, wherein the code is executable by the processor to:use a first set of resource blocks to transmit the uplink channel whenthe uplink channel comprises a Physical Uplink Control Channel (PUCCH)but not a Physical Uplink Shared Channel (PUSCH); and use a second setof resource blocks to transmit the uplink channel when the uplinkchannel comprises the PUSCH but not the PUCCH, the second set ofresource blocks being different than the first set of resource blocks.91. The computer-readable medium of claim 90, wherein the code isexecutable by the processor to: when the uplink channel comprises thePUCCH and the PUSCH, frequency division multiplex the PUCCH and thePUSCH on the uplink channel and, use a subset of less than all of thefirst set of resource blocks to transmit the PUCCH; and use at leastsome of the second set of resource blocks to transmit the PUSCH.
 92. Thecomputer-readable medium of claim 90, wherein the code is executable bythe processor to: when the uplink channel comprises the PUCCH and thePUSCH, frequency division multiplex the PUCCH and the PUSCH bypuncturing at least one frequency sub-carrier of at least one resourceblock of the first set of resource blocks to transmit at least part ofthe PUSCH.
 93. A method for wireless communication, comprising:associating a virtual cell identifier of a first base station withtransmissions between the first base station and a first user equipment(UE), wherein the virtual cell identifier is also associated withtransmissions between a second base station and a second UE; andidentifying a set of common resource blocks for transmission of ademodulation reference signal (DM-RS) in an uplink channel and adownlink channel between the first base station and the first UE, theidentification of the set of common resource blocks being based at leastin part on the virtual cell identifier.
 94. The method of claim 93,further comprising: identifying a first port associated with a firstspatial multiplexing for transmission of the DM-RS between the firstbase station and the first UE, wherein the first spatial multiplexing isdifferent from a second spatial multiplexing associated with a secondport used to transmit a DM-RS between the second base station and thesecond UE.
 95. The method of claim 94, further comprising: associating afirst link identifier with the uplink channel between the first basestation and the first UE, and associating a second link identifier withthe downlink channel between the first base station and the first UE,wherein the first link identifier is different from the second linkidentifier; and transmitting the first link identifier withtransmissions in the uplink channel or transmitting the second linkidentifier with transmissions in the downlink channel.
 96. The method ofclaim 95, wherein: transmitting the first link identifier withtransmissions in the uplink channel comprises generating the DM-RS as afunction of the first link identifier; and transmitting the second linkidentifier with transmissions in the downlink channel comprisesgenerating the DM-RS as a function of the second link identifier.
 97. Anapparatus for wireless communication, comprising: means for associatinga virtual cell identifier of a first base station with transmissionsbetween the first base station and a first user equipment (UE), whereinthe virtual cell identifier is also associated with transmissionsbetween a second base station and a second UE; and means for identifyinga set of common resource blocks for transmission of a demodulationreference signal (DM-RS) in an uplink channel and a downlink channelbetween the first base station and the first UE, the identification ofthe set of common resource blocks being based at least in part on thevirtual cell identifier.
 98. The apparatus of claim 97, furthercomprising: means for identifying a first port associated with a firstspatial multiplexing for transmission of the DM-RS between the firstbase station and the first UE, wherein the first spatial multiplexing isdifferent from a second spatial multiplexing associated with a secondport used to transmit a DM-RS between the second base station and thesecond UE.
 99. The apparatus of claim 98, further comprising: means forassociating a first link identifier with the uplink channel between thefirst base station and the first UE, and associating a second linkidentifier with the downlink channel between the first base station andthe first UE, wherein the first link identifier is different from thesecond link identifier; and means for transmitting the first linkidentifier with transmissions in the uplink channel or transmitting thesecond link identifier with transmissions in the downlink channel. 100.The apparatus of claim 99, wherein: the means for transmitting the firstlink identifier with transmissions in the uplink channel comprises meansfor generating the DM-RS as a function of the first link identifier; andthe means for transmitting the second link identifier with transmissionsin the downlink channel comprises means for generating the DM-RS as afunction of the second link identifier.
 101. An apparatus for wirelesscommunication, comprising: a processor; memory in electroniccommunication with the processor; and instructions stored in the memory,the instructions being executable by the processor to: associate avirtual cell identifier of a first base station with transmissionsbetween the first base station and a first user equipment (UE), whereinthe virtual cell identifier is also associated with transmissionsbetween a second base station and a second UE; and identify a set ofcommon resource blocks for transmission of a demodulation referencesignal (DM-RS) in an uplink channel and a downlink channel between thefirst base station and the first UE, the identification of the set ofcommon resource blocks being based at least in part on the virtual cellidentifier.
 102. The apparatus of claim 101, wherein the instructionsare executable by the processor to: identify a first port associatedwith a first spatial multiplexing for transmission of the DM-RS betweenthe first base station and the first UE, wherein the first spatialmultiplexing is different from a second spatial multiplexing associatedwith a second port used to transmit a DM-RS between the second basestation and the second UE.
 103. The apparatus of claim 102, wherein theinstructions are executable by the processor to: associate a first linkidentifier with the uplink channel between the first base station andthe first UE, and associating a second link identifier with the downlinkchannel between the first base station and the first UE, wherein thefirst link identifier is different from the second link identifier; andtransmit the first link identifier with transmissions in the uplinkchannel or transmitting the second link identifier with transmissions inthe downlink channel.
 104. The apparatus of claim 103, wherein: theinstructions executable by the processor to transmit the first linkidentifier with transmissions in the uplink channel compriseinstructions executable by the processor to generate the DM-RS as afunction of the first link identifier; and the instructions executableby the processor to transmit the second link identifier withtransmissions in the downlink channel comprise instructions executableby the processor to generate the DM-RS as a function of the second linkidentifier.
 105. A non-transitory computer-readable medium storingcomputer-executable code for wireless communications, the codeexecutable by a processor to: associate a virtual cell identifier of afirst base station with transmissions between the first base station anda first user equipment (UE), wherein the virtual cell identifier is alsoassociated with transmissions between a second base station and a secondUE; and identify a set of common resource blocks for transmission of ademodulation reference signal (DM-RS) in an uplink channel and adownlink channel between the first base station and the first UE, theidentification of the set of common resource blocks being based at leastin part on the virtual cell identifier.
 106. The computer-readablemedium of claim 105, wherein the code is executable by the processor to:identify a first port associated with a first spatial multiplexing fortransmission of the DM-RS between the first base station and the firstUE, wherein the first spatial multiplexing is different from a secondspatial multiplexing associated with a second port used to transmit aDM-RS between the second base station and the second UE.
 107. Thecomputer-readable medium of claim 106, wherein the code is executable bythe processor to: associate a first link identifier with the uplinkchannel between the first base station and the first UE, and associatinga second link identifier with the downlink channel between the firstbase station and the first UE, wherein the first link identifier isdifferent from the second link identifier; and transmit the first linkidentifier with transmissions in the uplink channel or transmitting thesecond link identifier with transmissions in the downlink channel. 108.The computer-readable medium of claim 107, wherein: the code executableby the processor to transmit the first link identifier withtransmissions in the uplink channel comprises code executable by theprocessor to generate the DM-RS as a function of the first linkidentifier; and the code executable by the processor to transmit thesecond link identifier with transmissions in the downlink channelcomprises code executable by the processor to generate the DM-RS as afunction of the second link identifier.
 109. A method for wirelesscommunication, comprising: dynamically selecting a configuration of anuplink channel for uplink communications in an unlicensed radiofrequency spectrum band; generating a waveform based on the selectedconfiguration; and communicating the generated waveform in a signal inthe unlicensed radio frequency spectrum band using the uplink channel.110. The method of claim 109, wherein: the configuration of the uplinkchannel is selected from an orthogonal frequency-division multipleaccess (OFDMA) configuration, a single carrier frequency-divisionmultiple access (SC-FDMA) configuration, and a resource blockinterleaved frequency-division multiple access (FDMA) configuration.111. The method of claim 109, further comprising: receiving signalingfrom a base station; and selecting the configuration of the uplinkchannel based at least in part on the received signaling.
 112. Themethod of claim 111, wherein the signaling from the base stationindicates a resource block allocation, and wherein the configuration ofthe uplink channel is selected based at least in part on the resourceblock allocation.
 113. The method of claim 111, wherein theconfiguration of the uplink channel is selected based at least in parton a modulation and coding scheme (MCS) indicated in a downlink grant orwhether an uplink multiple-input multiple-output (UL-MIMO)/multi-userMIMO (MU-MIMO) is enabled or disabled.
 114. An apparatus for wirelesscommunication, comprising: means for dynamically selecting aconfiguration of an uplink channel for uplink communications in anunlicensed radio frequency spectrum band; means for generating awaveform based on the selected configuration; and means forcommunicating the generated waveform in a signal in the unlicensed radiofrequency spectrum band using the uplink channel.
 115. The apparatus ofclaim 114, wherein the means for dynamically selecting the configurationof the uplink channel comprises: means for selecting the configurationof the uplink channel from an orthogonal frequency-division multipleaccess (OFDMA) configuration, a single carrier frequency-divisionmultiple access (SC-FDMA) configuration, and a resource blockinterleaved frequency-division multiple access (FDMA) configuration.116. The apparatus of claim 114, further comprising: means for receivingsignaling from a base station; and means for selecting the configurationof the uplink channel based at least in part on the received signaling.117. The apparatus of claim 116, wherein the signaling from the basestation indicates a resource block allocation, and wherein the means forselecting the configuration of the uplink channel comprises means forselecting the configuration of the uplink channel based at least in parton the resource block allocation.
 118. The apparatus of claim 116,wherein the means for selecting the configuration of the uplink channelcomprises means for selecting the configuration of the uplink channelbased at least in part on a modulation and coding scheme (MCS) indicatedin a downlink grant or whether an uplink multiple-input multiple-output(UL-MIMO)/multi-user MIMO (MU-MIMO) is enabled or disabled.
 119. Anapparatus for wireless communication, comprising: a processor; memory inelectronic communication with the processor; and instructions stored inthe memory, the instructions being executable by the processor to:dynamically select a configuration of an uplink channel for uplinkcommunications in an unlicensed radio frequency spectrum band; generatea waveform based on the selected configuration; and communicate thegenerated waveform in a signal in the unlicensed radio frequencyspectrum band using the uplink channel.
 120. The apparatus of claim 119,wherein the instructions executable by the processor to dynamicallyselect the configuration of the uplink channel comprise instructionsexecutable by the processor to: dynamically select the configuration ofthe uplink channel from an orthogonal frequency-division multiple access(OFDMA) configuration, a single carrier frequency-division multipleaccess (SC-FDMA) configuration, and a resource block interleavedfrequency-division multiple access (FDMA) configuration.
 121. Theapparatus of claim 119, wherein the instructions are executable by theprocessor to: receive signaling from a base station; and select theconfiguration of the uplink channel based at least in part on thereceived signaling.
 122. The apparatus of claim 121, wherein thesignaling from the base station indicates a resource block allocation,and wherein the instructions are executable by the processor todynamically select the configuration of the uplink channel based atleast in part on the resource block allocation.
 123. The apparatus ofclaim 121, wherein the instructions are executable by the processor todynamically select the configuration of the uplink channel based atleast in part on a modulation and coding scheme (MCS) indicated in adownlink grant or whether an uplink multiple-input multiple-output(UL-MIMO)/multi-user MIMO (MU-MIMO) is enabled or disabled.
 124. Anon-transitory computer-readable medium storing computer-executable codefor wireless communications, the code executable by a processor to:dynamically select a configuration of an uplink channel for uplinkcommunications in an unlicensed radio frequency spectrum band; generatea waveform based on the selected configuration; and communicate thegenerated waveform in a signal in the unlicensed radio frequencyspectrum band using the uplink channel.
 125. The computer-readablemedium of claim 124, wherein the code executable by the processor todynamically select the configuration of the uplink channel comprisescode executable by the processor to : dynamically select theconfiguration of the uplink channel from an orthogonalfrequency-division multiple access (OFDMA) configuration, a singlecarrier frequency-division multiple access (SC-FDMA) configuration, anda resource block interleaved frequency-division multiple access (FDMA)configuration.
 126. The computer-readable medium of claim 124, whereinthe code is executable by the processor to: receive signaling from abase station; and select the configuration of the uplink channel basedat least in part on the received signaling.
 127. The computer-readablemedium of claim 126, wherein the signaling from the base stationindicates a resource block allocation, and wherein the code isexecutable by the processor to dynamically select the configuration ofthe uplink channel based at least in part on the resource blockallocation.
 128. The computer-readable medium of claim 126, wherein thecode is executable by the processor to dynamically select theconfiguration of the uplink channel based at least in part on amodulation and coding scheme (MCS) indicated in a downlink grant orwhether an uplink multiple-input multiple-output (UL-MIMO)/multi-userMIMO (MU-MIMO) is enabled or disabled.